Oil Mist Monitoring Protocol - capp.ca

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Oil Mist Monitoring Protocol

December 2004

2005-0010

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The Canadian Association of Petroleum Producers (CAPP) represents 150

companies that explore for, develop and produce natural gas, natural gas liquids,

crude oil, oil sands, and elemental sulphur throughout Canada. CAPP member

companies produce more than 98 per cent of Canada’s natural gas and crude oil.

CAPP also has 125 associate members that provide a wide range of services that

support the upstream crude oil and natural gas industry. Together, these members

and associate members are an important part of a $75-billion-a-year national

industry that affects the livelihoods of more than half a million Canadians.

Disclaimer

This publication was prepared for the Canadian Association of Petroleum

Producers (CAPP) by BC Research Inc. and Certified Industrial Hygiene

Consulting Ltd. While it is believed that the information contained herein is

reliable under the conditions and subject to the limitations set out, CAPP, BC

Research Inc. and Certified Industrial Hygiene Consulting Ltd. do not guarantee

its accuracy. The use of this report or any information contained will be at the

user’s sole risk, regardless of any fault or negligence of BC Research Inc.,

Certified Industrial Hygiene Consulting Ltd., or CAPP or its co-funders.

Review by July 2010

December 2004 Oil Mist Monitoring Protocol Page i

Overview

Occupational exposure to oil mist is a common occurrence during oil well drilling

operations involving the use of invert mud. In addition, exposure to oil mist may

occur during the production and refining of crude oil. Exposure to lubricating oil

mist may also occur in locations where pumps and compressors are operating. Oil

mist spray poses occupational health and fire safety concerns, and suitable

sampling methods are required to assess and adequately control these hazards

effectively.

Objectives

The following project was undertaken in an effort to:

Outline the current difficulties in oil mist sample collection, analysis and

interpretation.

Recommend an air sample collection and analytical method(s) for use by the

petroleum industry for the evaluation of worker exposure to oil mist and fire

safety risk of this contaminant.

Outline the limitations of the sample collection and analytical method(s)

recommended for evaluation of worker exposure to oil mist.

Discuss how the results of the sampling can be interpreted with respect to both

occupational health and fire safety regulatory requirements.

Present a list of qualified laboratories that can analyze for oil mist in

accordance with the recommended method(s).

Interviews with representative laboratories and a review of the available literature

on oil mist composition, the health effects of exposure to various types of oil mist,

oil mist exposure standards and available sample collection and analytical

methods for oil mist and metal working fluids, has led to the following findings:

Composition

The composition of oil varies significantly with respect to hydrocarbon content

and additives. For instance, drilling fluids may be water based, or oil based. In oil

based drilling fluids, mineral oil, diesel, crude oils or synthetic oils may be

utilized. In addition, in the field these products may become contaminated with

other oil products further changing their composition.

Health Effects

Compositional differences between oil containing products influence potential

health outcomes of concern. For instance, mildly refined mineral oils contain

higher concentrations of polycyclic aromatic hydrocarbons compared with

severely refined mineral oils and as a result present a greater cancer risk.

Similarly, frac oils and drilling fluids may contain higher concentrations of

lighter hydrocarbons, such as benzene, toluene, ethylbenzene, xylene and hexane

and as a result present a higher risk of systemic toxicity, compared with straight

mineral oil.

December 2004 Oil Mist Monitoring Protocol Page ii

Exposure Standards

The exposure standards applicable in Western Canada are specific for straight

mineral oil containing products and are not applicable to products composed of

other oil fractions or with significant additives. The majority of mineral oil

exposure standards are 5 mg/m3 for an eight-hour exposure and 10 mg/m3 for a

15-minute exposure. However, British Columbia and the American Conference

for Governmental Industrial Hygienists (ACGIH) have lower exposure standards.

All of the exposure standards are for total aerosol (excluding the vapour phase),

except for the proposed ACGIH Threshold Limit Value which is for the inhalable

fraction. The metal working fluid exposure guideline from the National Institute

for Occupational Safety and Health (NIOSH) is applicable to a wider range of oil

types including straight, water-soluble, semi-synthetic and synthetic.

Recommendations

The differences in oil mist composition and health effects, combined with the

differences in exposure standards makes the selection of a single sample

collection and analytical method, and interpretation of sampling results a

challenge. In an effort to determine the most appropriate sample collection and

analytical method, all of the available sample collection and analytical methods

were reviewed for their advantages and disadvantages. Issues surrounding the

purpose of the sampling, sensitivity, which phase to collect, what size fraction to

collect, the applicability of method to other oil types, the ease of field collection

and storage, if or how co-contaminants are removed or accounted for, analytical

limitations, validation, cost, and how results will be interpreted were evaluated.

Recommendations are made below:

Prior to undertaking sampling activities, the following information should be

collected: the composition of the oil; for mineral oils, if the oil is severely or

mildly refined; a list of potential co-contaminants that may interfere with the

sampling method; and the purpose or objective of the sampling method.

For compliance sampling with the mineral oil mist exposure standards, it is

recommended that the sampling method required by the regulator be utilized if

specified. If a specific sampling method is not referenced in the regulations, it is

recommended that the recently approved NIOSH Sampling Method 5524 or the

ASTM Provisional Sampling Method for metal working fluids be utilized. These

samples methods are recommended as they remove inorganic co-contaminants,

they are applicable to a wide range of oil types, and they can be used as a

relatively inexpensive screening tool to determine whether further investigation is

required. Disadvantages of these methods include that they are not fully validated,

and they require a bulk sample of the oil be collected

Sample results for products composed primarily of mineral oils should be

compared to the appropriate mineral oil exposure standard. If sampling for metal

working fluids, and in the absence of an exposure standard, it is recommended the

results be compared with the NIOSH metal working fluid recommended exposure

limit. Sample results for products not composed primarily of mineral oil should

not be compared to the exposure standards for mineral oils.

December 2004 Oil Mist Monitoring Protocol Page iii

When a more detailed understanding of a worker’s exposure to oil is desired, it is

recommended that both the aerosol and the vapour phase of the oil be collected.

It is recommended that the aerosol phase of the oil be collected in accordance

with either the Provisional ASTM or NIOSH 5524 sampling methods as

mentioned above. For the vapour phase, it is recommended that a volatile organic

compound sampling method using an activated charcoal adsorption tube be

utilized to collect the samples with a pre-filter for contaminants removal, followed

by extraction with an appropriate solvent. Both extracts can then be analyzed by

gas chromatography flame-ionization or mass spectrometry.

Real time aerosol monitors may useful for some sampling scenarios, such as

exposure control evaluations, however, additional research is required before

utilizing this sampling method to ensure safety in potentially flammable

atmospheres and to determine the most appropriate instruments.

Laboratories

With respect to the selection of an appropriate laboratory, it is recommended that

an accredited laboratory be selected. All of the laboratories interviewed for this

project are capable of analyzing for oil mist and volatile organic compounds using

current mineral oil sampling and methods. However, some laboratories are using

alternative extraction solvents than those prescribed and these changes should be

verified before analysis of oil samples is undertaken. At this time the laboratories

interviewed, with the exception of McMaster University, are not aware of the

Provisional ASTM or NIOSH 5524 sampling methods for metal working fluids

and have not used either of these methods. However, these methods are within the

capabilities of the labs interviewed.

December 2004 Oil Mist Monitoring Protocol Page iv

Contents

1 Introduction .......................................................................................................... 1-1

1.1 Objectives ................................................................................................ 1-1

2 Methodology ........................................................................................................ 2-1

3 Classification of Oil Mists ................................................................................... 3-1

4 Health Hazards Associated with Oil Mists .......................................................... 4-1

5 Exposure Standards and Guidelines..................................................................... 5-1

6 Discussion of Critical Issues Regarding Sample Collection and

Analytical Methods .............................................................................................. 6-1

7 Conclusions .......................................................................................................... 7-1

8 Recommendations ................................................................................................ 8-1

8.1 Sample Selection Protocol ....................................................................... 8-1

8.2 Recommended Sampling Methods .......................................................... 8-1

8.2.1 Compliance Sampling .................................................................. 8-1

8.2.2 Investigative Sampling................................................................. 8-3

8.3 Laboratories ............................................................................................. 8-4

8.4 Additional Comments .............................................................................. 8-5

9 References ............................................................................................................ 9-1

List of Appendices

Appendix A Classification of Oils

Appendix B Health Effects of Oils

Appendix C Exposure Standards and Guidelines

Appendix D Sample Collection and Analytical Methods

Appendix E Summury of Sample Collection and Analytical Methods

Tables

Table 5-1 Oil Mist Exposure Standards and Guidelines ............................................... C-i

Table 6-1 Validated Oil Mist Sampling Methods ......................................................... D-i

Table 6-2 Alternate Oil Mist Sampling Methods ....................................................... D-iv

Table 8-1 Summary of Sampling and Analytical Methods ........................................... E-i

December 2004 Oil Mist Monitoring Protocol Page 1-1

1 Introduction

Occupational exposure to oil mist is a common occurrence during oil well drilling

operations involving the use of invert mud. Oil mist spray poses occupational

health and fire safety concerns, and suitable sampling methods are required to

assess and adequately control these hazards effectively. Drilling fluids invariably

contain various additives that may affect the hazard rating of the oil mist.

Polycyclic aromatic hydrocarbons may also be present to varying degrees. In

addition, other contaminants present, such as volatile hydrocarbons, may interfere

with oil mist sampling methods.

Other areas of the oil and gas industry in which exposure to oil mist may occur

include production and refining of crude oil. In addition, exposure to lubricating

oil mist may occur in locations where pumps and compressors are operating.

1.1 Objectives

The objectives of this project were to:

Outline current difficulties in oil mist sample collection, analysis and

interpretation.

Recommend an air sample collection and analytical method(s) for use by the

petroleum industry for the evaluation of worker exposure to oil mist and fire

safety risk of this contaminant.

Outline the limitations of the sample collection and analytical method(s)

recommended for evaluation of worker exposure to oil mist.

Discuss how the results of the sampling can be interpreted with respect to both

occupational health and fire safety regulatory requirements.

Present a list of qualified laboratories that can analyze for oil mist in

accordance with the recommended method(s).


2 Methodology

The following activities were undertaken in preparation of this report:

Collection and review of validated sampling methods published by the

following organizations:

Occupational Safety and Health Administration (OSHA)

National Institute for Occupational Safety and Health (NIOSH)

American Conference of Governmental Industrial Hygienists (ACGIH)

Workers’ Compensation Board of British Columbia (WCB BC)

American Society for Testing Methods (ASTM)

United Kingdom –Health, Safety and Environment(UK HSE)

A review of the published literature for oil mist sampling methods and issues

surrounding oil mist sampling.

A review of the exposure guidelines in Canada and the United States for oil

mist and metal working fluids.

A review of the rational for the oil mist and metal working fluid exposure

guidelines from NIOSH and the ACGIH.

A review of the literature for the composition of various types of oils,

including invert drilling fluids.

A review of the literature for the health effects associated with various types

of oil-containing products, including invert drilling fluids.

Interviews with key personnel at the following laboratories:

ALS Laboratories, Vancouver, British Columbia

Cantest Laboratories, Burnaby, British Columbia

Envirotest Laboratories, Edmonton, Alberta

McMaster University, Occupational and Environmental Health

Laboratory, Hamilton, Ontario

Interviews with key individuals in the following organizations:

General Motors Canada, Health and Safety Department

NIOSH

ACGIH

WCB BC


3 Classification of Oil Mists

According to the Merriam Webster Dictionary, oils are combustible substances,

smooth and greasy in texture, which are liquid or can easily be liquefied on

warming, are soluble in ether but not in water, and leave a greasy stain on paper

or cloth. Oils may be of mineral or vegetable origin.

Mineral oils are defined by the ACGIH as being composed of a complex mixture

of hydrocarbons derived from naturally occurring petroleum crude oils. The

specific composition of a mineral oil depends on the composition of the original

crude oil and the refining process. Mineral oils are typically composed of straight

and branched paraffins, naphthenic (cycloparaffin), and aromatic hydrocarbons.

They have a carbon number of 15 or more and boiling points in the range of

300°C to 600°C (10). Mildly refined mineral oils have been processed to remove a

portion of the polycyclic aromatic compounds found in the crude oil from which

they were derived. Severely refined mineral oils have been processed further so

that only a small percentage of the original polycyclic aromatic hydrocarbons

remain (1).

There is no universally accepted method for classifying oils. Typically, oil

containing products are classified according to their intended use or by the fact

that they share certain similar physical and chemical properties such as flashpoint,

vapour pressure, boiling point, carbon range or viscosity. The lack of a

universally accepted classification frequently results in oil products with differing

chemical compositions or physical properties being categorized into the same

groups by different organizations. It is therefore important to understand the

composition and properties of oil-containing products so that health outcomes of

concern and the most appropriate sampling method can be determined.

Drilling fluids, frac oils, lubricants, hydraulic oils, heating oils and metal working

fluids are all examples of oil-containing products that are defined by their

intended use. Within each of these product categories there are usually several

sub-categories. Some of these sub-categories may contain little or no mineral oil.

For instance, drilling fluids used in the petroleum industry can be water or oil

based (2). The liquid phase of water based drilling fluids is largely composed of

sea water or brine. The liquid phase of oil based drilling fluids on the other hand,

consists mainly of mineral oils (mildly or severely refined), diesel or similar

petroleum hydrocarbon fractions. Crude oil and natural gas condensate

hydrocarbons may also contaminate drilling fluids that have been circulated

down-hole. Diesel, crude oil and natural gas condensate differ from mineral oil in

composition and physical properties (2). Crude oil is composed of a complex

mixture of hydrocarbons that can be divided into different fractions including:

light ends (~2%); light, medium and heavy naptha (~34%); kerosene (~11%);

light gas oil (~21%); and heavy gas and residual oils (~31%) (3,4). There are two

basic types of hydrocarbons in crude oil, saturated and aromatic. Saturated

hydrocarbons, also called alkanes, paraffins or aliphatic hydrocarbons, may be

straight, branched or cyclic. Alkanes normally comprise 30% to 100% of the

hydrocarbons in crude oil, typically with carbon numbers between 1 and 78.

Aromatic hydrocarbons can account for between 1% and 20% of the total


hydrocarbons in crude oil. Some light crude oils may contain up to 50% aromatic

hydrocarbons. In addition, crude oil may contain small concentrations of

hydrocarbons substituted with sulphur, oxygen, or nitrogen, metals, and

asphaltenes (2,5). Diesel fuel is reported to consist of hydrocarbons having a

carbon number between 9 and 28, and boiling points in the range of 150°C to

390°C (6). Diesel Fuel No. 1 is typically composed of 12% paraffins, 44%

napthalenes and 44% aromatics (7). In addition, synthetic oils can also be used in

drilling fluids instead of mineral oils or diesel (8). Synthetic oils are composed of

hydrocarbons of known composition and purity and usually consist of a much

narrower range of hydrocarbons.

Metal working fluids can be classified as follows: straight, soluble, synthetic or

semi-synthetic. Soluble metal working fluids are composed of a water-oil

emulsion. Usually less than 10% of the product is composed of mineral oil (15).

Additives may be present in the above fluids to modify the density or viscosity, to

control microbial growth, to prevent corrosion, to make a product more resistant

to heat, or for other reasons. For example, when using drilling fluids, the drilling

fluid engineer tests the drilling fluid repeatedly and adjusts the composition to

compensate for changes in conditions as the well is drilled deeper. Drilling fluids

are frequently recycled for cost saving purposes, and this can result in an

accumulation of contaminants (2). The presence of additives and other

contaminants may be a significant issue with respect to potential health outcomes.

The choice of sampling method may be affected where this is the case.

More information on the composition of crude oil, drilling fluids, frac fluids,

mineral oils, lubricants and metal working fluids can be found in Table 3-1 in

Appendix A. This table is not intended to be complete. Rather the purpose is to

provide the reader with additional information on the differences between these

products.


4 Health Hazards Associated with Oil Mists

Inhalation of mineral oils at normal temperatures is commonly associated with the

mist phase. This is due to their composition, being made up of hydrocarbons with

carbon numbers of 15 or greater. Mineral oil mists are reported to be capable of

causing respiratory tract and eye irritation (9,10). At higher concentrations, mineral

oil mists have been reported to cause chemical pneumonitis, lipid pneumonia,

asthma and an increased prevalence of basal lung fibrosis (10).

Although mineral oil is commonly associated with the mist phase, some products

when heated, can produce appreciable amounts of vapour. The amount of vapour

depends on the exact composition of the mineral oil and the temperature.

According to Oil Companies’ European Organization for Environmental, Health

and Protection (CONCAWE) (1981), little information has been reported on the

effects of mineral oil vapour exposure, however, it is thought to be present at

higher concentrations than mineral oil mist but to be less toxic (9). According to

an alternate source, mineral oil vapour is tolerated at 500 parts per million (ppm)

to 1000 ppm, which is equivalent to several grams of oil mist per cubic metre of

air (11). CONCAWE indicates that mineral oil vapours are considered to be less

toxic than the mist because most of the vapour is exhaled. In comparison, it is

believed that the majority of inhaled mineral oil mist is deposited on the lung

tissue as droplets, which may then only be removed by clearance mechanisms or

by absorption into body fluids. Thus, mineral oil mists are believed to be capable

of causing both local and systemic toxic effects (9).

The International Agency for Research on Cancer (IARC) has reported that there

is sufficient evidence of carcinogenicity in experimental animals for several types

of mineral oils including vacuum distillates, mildly solvent refined, mildly

hydrotreated, mildly acid treated and aromatic distillate extracts. No evidence, or

insufficient evidence, of carcinogenicity in experimental animals has been

reported for severely solvent refined, severely hydrotreated, severely acid treated

and white oils (10). The International Agency for Research on Cancer also

concluded that there is sufficient evidence from human studies to classify

untreated or mildly treated mineral oils as carcinogenic, but that there is

insufficient evidence for highly refined mineral oils (10). Poorly refined mineral

oils derived from petroleum are reported to be capable of inducing skin and

scrotal cancers after prolonged, repeated, and heavy skin contact (10).

Products that are not composed primarily of mineral oil may have potential health

outcomes that differ from those of pure mineral oil. These health effects should be

considered when selecting an appropriate sampling method and when comparing

sampling results to exposure guidelines. For instance, some drilling and frac

fluids may contain higher concentrations of benzene, toluene, ethylbenzene and

xylenes (BTEX) compared to mineral oil (12). Light crude oils contain BTEX,

hexanes and possibly lighter hydrocarbons. The presence of these compounds will

result in a greater inhalation and fire hazard, and may pose an increased risk of

cancer, central nervous system effects, dermatitis and systemic organ effects

(liver and kidneys) (12). The health effects of some of these lighter hydrocarbons

are listed in Appendix B.


Drilling fluids composed of diesel-based products similarly may present an

increased risk of skin cancer, kidney damage, eye, skin and respiratory tract

irritation, dermatitis, central nervous system effects, and lung damage (if

aspirated) according to MSDS reviewed (13,14). However, the ACGIH in their

rational for the Diesel/Kerosene Threshold Limit Value indicate that diesel fuel is

an A3 (animal carcinogen), can cause lung damage if aspirated and may cause

dermatitis or local skin damage upon prolonged contact. They note that diesel fuel

has not been demonstrated to pose a significant inhalation hazard to humans (7).

Exposure to metal working fluids likewise has been associated with dermatitis,

occupational asthma and allergic alveolitis (9).

Additional information on the health outcomes of concern for drilling fluids,

crude oils, frac oils, lubricants, mineral oils, and metal working fluids can be

found in Figure 4-1 in Appendix B.


5 Exposure Standards and Guidelines

Table 5-1 in Appendix C presents the occupational exposure standards for oil mist

in applicable Canadian jurisdictions. In addition, exposure standards and

guidelines from the United States have been included for comparison.

With the exception of British Columbia, current exposure standards or guidelines

for mineral oil mist are 5 milligrams per cubic metre of air (mg/m3) for an eight-

hour time weighted average (TWA) exposure and 10 mg/m3 for short term or

15-minute exposure.

The American Conference of Governmental Industrial Hygienists in their

Documentation of Threshold Limit Values and Biological Exposure Indices

(TLVs and BEIs) (2001), state that the recommended TLVs for Oil Mist, Mineral

are based on the collection of mineral oil mist by a method that does not collect

vapour. The TLVs are intended to prevent the potential for respiratory tract

irritation, and more serious respiratory health effects of chemical pneumonitis and

lipoid pneumonia. They sate the TLVs may not be suitable for all mineral oils,

and may not adequately protect workers exposed to mineral oils that contain

additives, contaminants or potential carcinogenic fractions. For these oils,

measuring the individual additives, contaminants or carcinogens may be more

appropriate (10).

The ACGIH has proposed in the notice of intended changes for 2003 to lower the

TWA-TLV for mineral oil mist to 0.2 mg/m3 (inhalable fraction). This change is

recommended based on mildly refined mineral oil being listed as a suspected

human carcinogen (A2). Highly refined oils are classified by the ACGIH as

possible human carcinogens, which cannot be classified conclusively because of a

lack of data (A4) (39).

The recommendation by the ACGIH to lower the TLV for mineral oil mist is in

line with current Exposure Limits in British Columbia. Currently in British

Columbia, the eight-hour Exposure Limit for mildly refined mineral oils is

0.2 mg/m3. Mildly refined mineral oils are defined as including untreated oils,

aromatic distillate extracts, and oils that have been mildly solvent refined, mildly

hydrotreated, mildly acid treated or catalytically cracked. Mildly refined mineral

oils in British Columbia are listed as confirmed human carcinogens, and exposure

to these oils should be kept as low as reasonably achievable. The carcinogen

designation is based on the presence of polycyclic aromatic hydrocarbons in

unrefined or mildly refined mineral oils (32).

Severely refined mineral oils in British Columbia have an eight-hour Exposure

Limit of 1 mg/m3. This category includes white oils, as well as those oils that

have been severely solvent refined, severely hydrotreated, or severely acid

treated. Severely refined mineral oils do not contain polycyclic aromatic

hydrocarbons in measurable quantities (32).

The National Institute for Occupational Safety and Health recommended a

thoracic standard of 0.4 mg/m3 for metal working fluids in 1998. This

recommendation was based on the potential for work-related asthma,


hypersensitivity pneumonitis and other adverse respiratory symptoms. In their

recommendations, they state that exposures should be kept as low as reasonably

achievable as symptoms have been reported at concentrations less than the

proposed standard. However, limitations of the sampling and analytical method

preclude a lower inhalation standard (15).

The Independent Lubricant Manufacturers Association has suggested to the

National Institute for Occupational Safety and Health that a Short Term Exposure

Limit or a Ceiling Limit of 2 mg/m3 may be more protective of worker health and

safety than a TWA Exposure Limit. The NIOSH has stated in “Criteria for a

Recommended Standard: Occupational Exposure to Metal Working Fluids” that a

Short Term Exposure Limit or Ceiling Limit would be burdensome, as it would

require considerably more sampling to assess compliance (15).

The exposure standards listed in this report apply to mineral oil based products.

They may be used for guidance purposes with other types of oil mist where

deemed appropriate. Drilling fluids composed primarily of water should not be

compared to these standards. In complex fluids, the health risk posed by

individual components, including additives, may need to be evaluated.


6 Discussion of Critical Issues Regarding Sample Collection and Analytical Methods

A large number of sample collection and analytical methods exist in the literature

for the determination of mineral oil mist concentrations. However, most situations

in the oil/gas well drilling, well completion, workover and production industries

also involve exposure to other volatile hydrocarbons. As such, the literature

methods are applicable to only one part of the issue. The interpretation of the

sampling results will not be as straight forward as for straight mineral oil

exposures, and other forms of sampling conducted concurrently may be advisable.

The most common sampling method employed to collect mineral oil mist is the

use of a sampling pump equipped with either a mixed cellulose ester, glass fibre,

polyvinyl chloride, or polytetrafluoroethylene filter. Total oil mist is most

commonly sampled using either a standard 37 mm diameter sampling cassette in

open or closed faced configuration, or an IOM sampler. However, some sampling

methods have used IOM samplers, cyclones or cascade impactors to collect

specific aerosol size fractions. Other sampling methods reported in the literature

for the collection of mineral oil mist include the use of midget impingers and

electrostatic precipitators.

Most sampling methods reported in the literature are designed to collect only the

aerosol phase of the oil generated and not the vapour phase. However, some

sampling methods reported have employed the use of a charcoal tube or Tenax

tube in line with a filter cassette to collect the oil vapour present in addition to the

aerosol (16,17).

Analytical methods reported in the literature include gravimetric analysis, or

spectroscopic analysis by infrared, ultraviolet or fluorescence. If the vapour phase

is collected, it is normally analyzed by gas chromatography coupled with either a

flame ionization detector or a mass spectrometer (16,17).

Other analytical methods reported in the literature include analysis of marker

compounds such as zinc, sodium, potassium, and boron commonly found in many

industrial oils. Concentrations of these additives are determined through analysis

by atomic absorption spectrophotometry or similar method (30).

In addition to the time-weighted average sample collection and analytical

methods, real time aerosol monitoring methods are also reported to be in use by

some industrial hygiene groups at larger corporations (18). In these companies,

side-by-side sampling has been conducted in order to correlate the real time

monitoring data with the results of time-weighted average sampling methods.

Table 6-1 in Appendix D compares validated time-weighted average sampling

methods for the collection and analysis of mineral oil mist used in Canada and the

United States.


Table 6-2 in Appendix D presents additional time-weighted average sample

collection and analytical methods for mineral oil mist and straight metal working

fluids.

It is beyond the scope of this report to outline in detail the issues with each

sampling and analytical method for mineral oil mist, therefore, a summary of the

sample collection and analytical methods, concerns with each method, and

perceived advantages and disadvantages of each combination of sampling and

analytical method is presented in Table 6-3 in Appendix E. The information used

to create this summary table was derived from a review of available sampling

methods and issues documented in the literature.

In selecting an appropriate sampling and analytical method, the following items

were identified as the critical issues to be addressed:

Sensitivity

Ideally the sampling method recommended should be capable of detecting, as a

minimum, 50% of the lowest exposure standard, preferably 25%. The lowest

exposure standard for oil mist currently available is 0.2 mg/m3, therefore the

lower limit of detection should correspond to 0.1 mg/m3 or less.

For acute health effects, some jurisdictions have 15-minute exposure standards of

10 mg/m3. For short-term monitoring in these jurisdictions, the lower limit of

detection should correspond to 5 mg/m3 or less.

Oil Mist Versus Vapour Phase

The exposure limits in all jurisdictions are based on the collection of mineral oil

aerosol on a filter. In some jurisdictions they acknowledge that this method may

underestimate the amount of oil mist present due to evaporative losses from the

filter. A reduction in the sampling volume and sampling time can be used to

decrease the evaporative losses at the cost of losing sensitivity. Alternative

options for minimizing inaccuracies due to evaporative losses include collecting,

extracting and analyzing a marker present in the oil that does not evaporate, or

using an electrostatic precipitator that has less evaporative losses.

The UK HSE are currently using a chemical marker method for straight metal

working fluids, However, reproducibility of results appears to be problematic at

this stage. This method also requires a collection of a bulk sample of the oil,

which may not always be possible.

Electrostatic precipitators currently are not readily available on the market as

personal monitors and may not be intrinsically safe.

Alternative sampling methods, including vapour collection, may be appropriate

for mineral oils containing lighter fractions, where evaporative losses may be

higher. Note that it is not appropriate to combine the oil mist and oil vapour

concentrations when determining a worker’s exposure as exposure standards for

oil mist do not include the vapour phase.


Options for collection of the vapour phase include:

filter collection in series with an organic vapour adsorption tube (e.g. charcoal

tube), and

separate sampling trains for the mist and the vapour phases, using either a

charcoal tube with pre-filter or a passive diffusion monitor for the vapour

phase.

Combining the two collection media into a single sampling train, as in the first

method, causes a compromise in the sampling flow rate. In many cases it would

be desirable to sample the oil mist at a flow rate greater than those recommended

(1 – 3 L/min) for optimum sensitivity . However, this flow rate cannot be used

with standard charcoal tubes, even the larger 400/200 milligrams (mg) type.

Charcoal tubes are commercially available up to 1800/200 mg (SKC 226-16-02),

and no doubt larger ones could be constructed by the laboratory of choice.

However, such large charcoal tubes require larger volumes of carbon disulphide

for elution, requiring modifications to the analytical technique.

The use of separate sampling trains eliminates the above problems, as each can be

run at its optimum flow rate. Passive organic vapour badges work well enough in

hydrocarbon vapour environments, but the writers did not find any information

assessing their performance in the presence of oil mist, which may coat the

outside of the vapour barrier, and alter vapour uptake rates.

Applicability of Method to Oil Types

Occupational exposure standards refer specifically to mineral oils. Therefore, the

exposure standards for mineral oil mist should be applied only those oils

composed primarily of mineral oil. Exposure standards exist for both severely and

mildly refined mineral oil in some jurisdictions. Mildly refined mineral oils have

been shown to be carcinogenic due to their polycyclic aromatic hydrocarbon

content and therefore have a lower exposure standard. Measurement of

polycyclic aromatic hydrocarbon content may or may not be necessary depending

on availability of information on the level of refinement of the oil from the

Material Safety Data Sheet or the manufacturer.

The National Institute for Occupational Safety and Health has proposed a

recommended exposure standard for metal working fluids which may be

appropriate for soluble, semi-synthetic and synthetic oils.

Co-contaminants

The collection of mineral oil mist using a filter method normally results in the

collection of other inorganic and non-volatile organic co-contaminants. The

method selected for sample collection and analysis should prevent the collection

of these co-contaminants or remove them prior to analysis.


If a filter method of collection is utilized, extraction with a solvent can help to

eliminate inorganic contaminants such as solid particulates that can result in a

positive bias in the sampling results. However, it is important to select the

appropriate solvent for the extraction. Ideally, the solvent selected should remove

only the hydrocarbons of interest, should not degrade the filter, should have good

recovery rates, should be of relatively low toxicity and be environmentally

friendly.

A bulk sample of the mineral oil for prior analysis can help to determine the most

suitable eluting solvent. However, collection of a bulk sample is not possible in

some cases. More than one bulk sample may be required if there are multiple

sources contributing to the oil mist in the air.

Practical Aspects of Field Use

Ideally the sampling method chosen should be relatively easy to use in the field,

should collect samples that are stable and do not require special handling, should

avoid the use of fragile sample collection equipment, be intrinsically safe, and

minimize discomfort or interference with worker activities.

Analytical Method

The most common analytical method used is gravimetric analysis. This method

alone, while simple and inexpensive, does not remove common co-contaminants

and can result in a positive bias in sample results. In an adaptation of this method

a solvent is used to extract the mineral oil from the filter, followed by evaporation

of the solvent and gravimetric analysis of the remaining material (presumed to be

oil mist). This method is advantageous in that it removes co-contaminated

particulate matter. However, similar to the spectroscopic analytical methods

described below, this method cannot differentiate between the other hydrocarbon

co-contaminants of similar molecular weight to mineral oil. For both of these

methods, if the extraction solvent varies between samples, the results may not be

directly comparable.

Other analytical methods include extraction of the mineral oil using a solvent

followed by spectroscopic analysis using infrared, ultraviolet or fluorescence

methods. The ultraviolet and fluorescence spectroscopic analytical methods rely

on mineral oil mist absorbing or fluorescing at a certain wavelength. Other

hydrocarbons with similar absorption of fluorescence wavelengths can positively

bias the result. An alternative method is NIOSH Method 5026, which uses

infrared spectrophotometry. A limitation of these methods is that they can only be

used for straight mineral oils. The method is not appropriate for soluble oils or

semi-synthetic oils which contain water, as the water causes turbidity, which

effects the amount of light able to pass through to the detector. Another problem

with this method is that the solvents used for extraction, carbon tetrachloride and

freon, are ozone-depleting substances, and are therefore difficult to obtain.

The use of a marker compound, such as zinc, sodium, potassium, or boron, for

determining the concentration of metal working fluids shows promise as it could

be used for straight oils, water soluble oils, semi-synthetic oils and synthetic oils.

However, the method is more complex from a collection and analysis perspective.


In addition, it is reported that further work is necessary to improve the accuracy of

the method.

Analytical Time and Costs

The analytical method selected would ideally be capable of being performed for a

reasonable cost and have good turn around times.

Methods which require the analysis of bulk samples, the analysis of polycyclic

aromatic hydrocarbons, or the analysis of the vapour phase add complexity to the

sampling and analytical method which increases both analytical costs and time.

Validation

Ideally the method chosen would have been validated for accuracy, precision and

the concentration range over which the method is applicable.

Several validated sampling methods for the aerosol component of mineral oil or

metal working fluids exist. Validation of the ASTM International Sampling

Method is not complete at the time of writing this report.

Validated methods exist for the sampling of hydrocarbon vapours.

Interpretation

The sampling and analytical method selected should yield results that can be

interpreted in a meaningful way. This is extremely important when comparing to

exposure standards, but also when considering health effects. It is important to

understand what is being measured, why it is being measured and what the results

are going to be compared against. Safety and/or hygiene technicians require clear

instruction on how to interpret the results.

Purpose of Sampling

The purpose of sampling often determines the type of samples collected and

analyzed. For instance for compliance purposes, total aerosol may be collected

and analyzed gravimetrically. If the concentration is below 50% of the applicable

exposure standard, additional analysis is not required. On the other hand, for a

research project, a more detailed analysis may be desired.

When analyzing samples for mineral oil mist, it may be worthwhile ensuring, as a

minimum, that an analytical method that removes co-contaminants is utilized,

even when the concentration is low. This will ensure that the data recorded is

actually for mineral oil mist and does not include inorganic co-contaminants.

Setting a minimum sampling and analytical standard such as this will ensure the

data collected is meaningful for comparative purposes (for example

epidemiological studies).

Size Fraction

The sampling method selected should collect the aerosol size fraction of concern

with respect to health effects. However, the size fraction collected should also

allow meaningful comparison to the occupational exposure limit applicable in that

jurisdiction. For instance, results of inhalable fraction monitoring cannot be

compared to an exposure standard which assumes total particulate monitoring.


Currently, most of the exposure limits for mineral oil are based on total aerosol.

However, care must be taken in interpreting the term total aerosol. In British

Columbia the sampling method for oil mist calls for an open-face sampling

cassette, while in other jurisdictions the same term applies to a close-face

sampling cassette. This difference is important when comparing sampling

methods between jurisdictions or when looking at historical sampling results.

All of the sampling methods listed in this report specify total particulate sampling,

with the exception of the NIOSH method for metal working fluids. Sampling of

the thoracic fraction is required in this method. However, NIOSH provides a

conversion factor, based on a single study, to allow for an approximate conversion

between total and thoracic sample results.


7 Conclusions

Based on a review of available data, conclusions are as follows:

All of the sampling methods can be utilized for the analysis of straight mineral

oil products. The UK HSE Sampling Method MDHS 95, the NIOSH

Sampling Method 5524, and the ASTM Provisional Sampling Method which

are all for metal working fluids, are reported to be applicable for straight,

soluble oils, semi-synthetic and synthetic oil containing metal working fluids

(wider application).

All of the sampling methods have similar lower detection limits of about

100 micrograms. They are sensitive enough for shift-length samples, a sample

volume of one cubic metre being required for a lower detection limit of

0.1 mg/m3. This is equivalent to 2% of the Alberta and Saskatchewan eight-

hour Exposure Limits, and 50% of the British Columbia Exposure Limit for

mildly refined mineral oil mist of 0.2 mg/m3. The required sample volume can

be achieved at a flow rate of 2.1 L/min over eight hours. The same flow rate

enables a detection limit equivalent to approximately 30% of the 15-minute

exposure standards in both Alberta and Saskatchewan (10 mg/m3).

Improvements in sensitivity can be achieved through higher sampling flow

rates.

All of the sampling methods remove particulate co-contaminants, with the

exception of the 1998 NIOSH sampling method described in the “Criteria for

a Recommended Standard: Occupational Exposure to Metal Working Fluids”.

However this is being replaced with NIOSH Sampling Method 5524, which

does remove inorganic co-contaminants. The spectroscopic sampling methods

(WCB 3201, NIOSH 5026, and OSHA ID-128) exclude some hydrocarbon

co-contaminants, provided they are not in the same absorption or fluorescence

wavelength range. None of the other sampling methods remove or separate

hydrocarbon co-contaminants.

Only the Enviro-Test method SOP #3.01 enables an assessment of the carbon

range of the particulate collected, potentially allowing exclusion of carbon

numbers corresponding to higher volatility hydrocarbons, not normally

considered to be part of oil mist

None of the sampling methods, with the exception of the UK HSE Sampling

Method MDHS 95, attempt to minimize or take into account evaporative

losses from the sampling filters during collection and storage.

None of the sampling methods recommended for compliance purposes collect

the vapour phase of mineral oil. All of the methods, strictly collect the aerosol

phase of the mineral oil.

All of the sampling methods reviewed collect the total particulate fraction of

the oil aerosol with the exception of the NIOSH sampling methods for metal

working fluids, which specifies collection of either the thoracic or total

fraction.


8 Recommendations

Based on a review of the types of oil products used in the petroleum industry and

the available sampling methods, it is not possible to recommend a single sampling

method suitable for all applications. Therefore a sample selection protocol and

two sample and analytical options are recommended

8.1 Sample Selection Protocol

Step 1: Determine the composition of the oil through reference to the Material

Safety Data Sheet, discussion with the manufacturer or analysis of a bulk

sample. The following sampling methods are applicable to products

composed primarily of mineral oil. Alternative sampling methods may be

more appropriate for products composed of ingredients other than mineral

oil, for example volatile hydrocarbons or water.

Step 2: Determine if the mineral oil is mildly or severely refined. If the type of

mineral oil cannot be determined, a bulk sample oil should be analyzed for

the presence of polycyclic aromatic hydrocarbons. Alternatively, the oil

can be assumed to be mildly refined, and the more stringent of the

exposure standards applied. Oils which contain less than one percent of

three to seven ring, or <0.1 percent of four to six ring polycyclic aromatic

hydrocarbons are reported by the American Petroleum Industry to present

a low carcinogenic potential and therefore may be considered to be

severely refined.

Step 3: Identify if there are any co-contaminants present in the area where the

mineral oil is being used that may interfere with the sampling method.

Step 4: Determine the purpose of the sampling. If the sampling is being conducted

for compliance purposes, a validated sampling method for mineral oil mist

should be utilized so that the results can be compared with the exposure

standards. If the sampling is being conducted for other purposes, such as

determining those factors that contribute to a worker’s exposure, testing

the effectiveness of exposure controls, or as part of a health study,

alternative sampling methods may be more appropriate.

8.2 Recommended Sampling Methods

8.2.1 Compliance Sampling

The sampling method recommended by the regulator in the jurisdiction where the

samples are being collected should be utilized if specified when sampling for

compliance. In Alberta, current regulations require that sampling and analytical

methods be in accordance with the NIOSH Manual of Analytical Methods or

otherwise acceptable to Workplace Health and Safety. The WCB BC

Occupational Health and Safety Regulation specifies that exposures are to be

evaluated using sampling methods acceptable to the Board. Recently due to

changes at the WCB BC, the sampling methods developed by the WCB BC are no

longer being maintained and it is advised alternative methods be utilized.


If a specific sampling method is not referenced in the regulations, it is

recommended that the recently approved NIOSH Sampling Method 5524 (soon to

be available to public) or the ASTM Provisional Sampling Method (in the process

of being approved) for metal working fluids be utilized. This sampling method

involves collection of the aersolized oil mist on a 37 mm polytetrafluoroethylene

(PTFE) filter held in a closed face cassette, and separation of the aerosol from co-

contaminated particulate matter via solvent extraction of the aerosol from the

filter. The solvent is then evaporated off and the residual fluid (assumed to be oil)

is analyzed gravimetrically.

Although this method is not fully validated, it is recommended for the following

reasons:

It removes particulate co-contaminants that can positively bias the sampling

results. This is especially important in those jurisdications with lower

exposure standards.

The sampling method is applicable to a wider range of oil-containing products

compared with other methods which are designed only for straight mineral

oils. Therefore, if two oil mists from two different sources were sampled

simultaneously on a single filter, this method would extract both oil mists

from the filter and accumulate them in the results. It is the use of a ternary

blend of dichloromethane, methanol and toluene and a binary blend of

methanol and water for the extraction step, which allows this method to

dissolve straight, soluble, semi-synthetic and synthetic oils in a single step.

It can be used as a relatively inexpensive screening tool to determine whether

further investigation is required. For example, 50% of the applicable exposure

limit may be used as a cut-off for further sampling.

The one disadvantage of this method is that it requires a bulk sample of the oil be

collected to conduct a solubility test.

When interpreting the sampling results, those products composed primarily of

mineral oils should be compared to the appropriate mineral oil exposure standard.

If sampling metal working fluids composed of soluble, semi-synthetic or synthetic

oils, and in the absence of an exposure standard for these types of materials, it is

recommended that the results be compared with the NIOSH metal working fluid

recommended exposure limit. Note that if sampling metal working fluids, either

the thoracic or total oil mist can be sampled. If the total oil mist is sampled, the

resulting concentration must be converted as discussed in the method for

comparison with the recommended exposure limit.

Note that collection of the vapour phase is not recommended for compliance

sampling as the exposure standards are based on the aerosol fraction. Collection

of the vapour phase, and adding it to the aerosol fraction collected will positively

bias the measured concentration.


Although the Provisional ASTM and NIOSH 5524 methods can be used to collect

and analyze soluble, semi-synthetic and synthetic oils, it is not appropriate to

compare the results for these products to the mineral oil exposure

standards/guidelines if the product is not primarily composed of mineral oil.

8.2.2 Investigative Sampling

In some cases, a more detailed understanding of a worker’s exposure to oil

products may be desired, such as in a complex environment where several

hydrocarbon sources are present simultaneously or when conducting a health risk

assessment. In these scenarios, it may be desirable to know the concentrations of

both aerosol- and vapour-phase hydrocarbons in air, to be able to identify other

hydrocarbon fractions present, or to identify specific chemical compounds of

interest. For these scenarios, it is recommended that both the aerosol and the

vapour phase of the oil be collected using two separate sampling trains. (Sampling

in series is not recommended as the flow rate for the vapour-phase method is

significantly lower than that for the aerosol, and would reduce the sensitivity of

latter method significantly).

It is also recommended that vapour samples be collected if investigators are

concerned about flammability issues. Vapours present from oils or other co-

contaminants present are a potential fire risk at sites. Oil mist, while it may

contribute to a fire once ignited, is unlikely to be the ignition source. If sampling

of vapours is conducted, areas where there is the potential for vapour

accumulation should be sampled, not personal or general ambient samples.

It is recommended that the aerosol phase of the oil be collected in accordance

with either the Provisional ASTM or NIOSH 5524 sampling methods as outlined

in Section 8.2.1 above. For the vapour phase, it is recommended that a volatile

organic compound sampling method using an activated charcoal adsorption tube,

such as NIOSH Sampling Methods 1500, 1501 or 2549, be utilized to collect the

samples. A pre-filter is recommended before the vapour phase sampling tube in

order to prevent aerosols, both solid and liquid, from contaminating the sampling

tube. Since workers would be required to wear two sampling trains, it seem

important to minimize inconvenience by using sampling pumps which as small as

possible.

Following sample collection, the aerosol filter may be extracted using either the

Provisional ASTM or NIOSH 5524 methods. The vapour phase should be

extracted in accordance with carbon diosulphide or other solvent specified in the

chosen volatile organic compound sampling method selected. The extracts can

then be analyzed by gas chromatography with a flame-ionization (GC-FID) or

mass spectrometry (GC-MS) detector. EnviroTest Laboratories method

SOP# 3.01 is referenced as an example of a suitable GC-FID method. Only the

EnviroTest method SOP #3.01 enables an assessment of the carbon range of the

particulate collected, permitting exclusion of carbon numbers corresponding to

higher volatility hydrocarbons, not normally considered to be part of oil mist.

In some cases, it may be important to investigate the causes of exposure or the

effectiveness of exposure control measures for oil mist. In such cases direct-


reading equipment measuring relative concentrations may be useful. Real time

aerosol monitors may be especially useful for these scenarios provided that they

are intrinsically safe. NIOSH suggests that real time monitoring may be feasible

as an alternative to time weighted average samples for the analysis of metal

working fluids. Additional research is required before utilizing this sampling

method to ensure safety in potentially flammable atmospheres and to determine

the most appropriate instruments. For quantitative use, NIOSH recommend that

these instruments should be calibrated by comparing them to gravimetric

techniques for each combination of aerosol size and fluid type (15). General

Motors currently uses the DataRam, a TSI Dust Track monitor, to monitor metal

working fluid mist levels. The DataRam is equipped with an airwash system over

the lens so that the oil does not condense or fog up the lens (18). Note that an

evaluation of all available direct reading aerosol monitors was not conducted as a

part of this review and several direct reading instruments from different

manufacturers may be appropriate for this type of sampling.

With respect to development sample collection strategies for oil mist sampling, it

is recommended that the NIOSH Occupational Exposure Sampling Strategy

Manual be reviewed (19).

8.3 Laboratories

With respect to the selection of an appropriate laboratory, it is recommended that

an AIHA accredited laboratory be selected for quality control assurance.

The laboratories interviewed as part of this project are all capable of analyzing for

oil mist and volatile organic compounds using standard sampling methods from

NIOSH, WCB BC or OSHA. However, for a variety of reasons, some of the

laboratories have conducted their own studies and selected alternative extraction

solvents than those prescribed in these methods. Prior to using a laboratory for

one of these methods, individuals should clarify any changes the laboratory has

made to the sampling method and a request a copy of any internal studies they

have conducted on how the alternate solvent compares to the recommended

solvent.

At this time the laboratories interviewed, with the exception of McMaster

University, are not aware of the Provisional ASTM or NIOSH 5524 sampling

methods for metal working fluids and have not used either of these methods.

Having stated this, the analytical method utilized by both these methods is not

complex and is within the capabilities of all of the labs interviewed. Several

hygiene laboratory web sites, such as Galson Laboratories and the Wisconsin

Occupational Health Laboratory, are recommending the Provisional ASTM

method to their clients.

As NIOSH has only recently adopted Sampling Method 5524, no AIHA

accreditation is currently available. Therefore it is important to ensure that the

laboratory selected has an appropriate internal quality control program until such

time that an accreditation process is available.


8.4 Additional Comments

McMaster University’s Occupational and Environmental Health Laboratory

currently has a grant from the Ontario Workplace Safety and Insurance Board to

conduct a study on sampling and analytical methods for metal working fluids, and

to recommend an appropriate sampling and analytical method. The results of this

study are expected to be published next year and may be of interest to CAPP

members.

Appendix A Classification of Oils

December 2004 Oil Mist Monitoring Protocol Page A- i

Oil Type Composition

Crude Oil General Crude oil is a complex mixture of hydrocarbons (2). Crude oil is reported to be composed of various fractions of different boiling point ranges. The major fractions are defined as: light ends (~2%); light, medium and heavy naptha (~34%); kerosene (~11%); light gas oil (~21%); and heavy gas and residual oils (~31%) (3,4).

Most crude oils contain 50% to 98% hydrocarbons. There are two basic types of hydrocarbons in crude oil, saturated and aromatic. Olefins are rarely found in crude oils. In addition, crude oil may contain smaller concentrations of hydrocarbons substituted with sulphur, oxygen, or nitrogen. Small concentrations of metals, such as vanadium and nickel, may be present as either organic metal complexes or as inorganic salts. Asphaltenes are normally present between 0.2% and 3.2%. Asphaltenes are high molecular weight, polar compounds consisting of sheets of condensed aromatic ring structures (2,5).

Saturated hydrocarbons, also called alkanes, paraffins or aliphatic hydrocarbons, may be straight, branched or cyclic. Alkanes normally represent 30% to 100% of the hydrocarbons in crude oils. Cyclic alkanes are the most abundant, followed by straight and branched chains. Generally these are in the range of C1 to C78. Alkenes or olefins are rare in crude oils (2).

Cyclcoalkanes, also called cycloparaffins or napthanes, may represent more that 50% of the total hydrocarbons in crude oil. Most are derivatives of cyclcopentane or cyclohexane (2).

Aromatic hydrocarbons can account for between 1% to 20% of the total hydrocarbons in crude oil. Some light crude oils may contain up to 50% aromatic hydrocarbons (2). These include benzene, toluene, ethylbenzene, xylene, triethyl benzenes, other soluble benzenes and other polycyclic aromatic hydrocarbons.

Paraffinic Characterized by high wax content, high natural viscosity index (rate of change in viscosity over a given temperature range), and relatively low aromatic content (includes some polycyclic aromatic hydrocarbons) (20)

Napthalenic Low in wax content, relatively high in cycloparaffins and aromatic hydrocarbons (including some polycyclic aromatic compounds), low viscosity index (20,21).

December 2004 Oil Mist Monitoring Protocol Page A- ii


Drilling Muds (Drilling Fluids)

General A wide variety of drilling fluids exist. The drilling fluid utilized, depends on the requirements for each well. Components include a liquid phase (which can be oil, water or synthtetic based), various mud products added to achieve desired physical and chemical properties, drill solids, and possibly barite or other solids used as weighting agents.

During drilling, the drilling mud engineer tests the drilling mud repeatedly and adjusts the composition to compensate for changes in conditions as the well is drilled deeper. In addition, due to the cost, most drilling muds are recycled until they are no longer usable. Therefore, drilling muds may contain contaminants resulting from the drilling process, especially formation fluids (2). During circulation down-hole drilling fluids commonly absorb light hydrocarbons from the formation fluid, including benzene and other aromatic compounds.

Non Aqueoous (Oil Based)

For non-aqueous drilling fluids, the liquid phase is composed of an oil usually in the range of 80% to 100% of the total drilling fluid composition. It is the major contributor to the overall chemistry and properties of the fluid. Many types of base oils have been used ranging from produced crude oils, diesel and various commercial distillates, to highly refined mineral oils. The properties and specific chemical composition of these oils depend on the original crude stock and the refining process used to produce them.

Most oil base drilling fluids include an organic oil wetting surfactant to ensure all surfaces are strongly oil wet. Organophilic clay (amine treated bentonite) is used to build viscosity. Other polymeric products may also be used to adjust viscosity. Invert oil base mud contains an internal brine water phase designed to dehydrate shale formations with lower water salinity. A soluble salt may be used to maintain a specified brine concentration. Additional organic surfactants are used to ensure the brine water is held as the internal phase of the emulsion. Lime is often used to assist the emulsifying agents.22 Some drilling fluids are highly refined, with very low content polycyclic aromatic hydrocarbons. Mineral oils used as drilling muds contain small concentrations of polycyclic aromatic hydrocarbons (<1.6% in one report). Mineral oils are reported to contain fewer aromatic compounds compared to diesel. The Industry Recommended Practice 14.1 produced by the Drilling and Completions Committee of the Canadian Association of Petroleum Producers in 2001 reported total polycyclic aromatic hydrocarbons in oil based drilling fluids of up to 3.4% by weight. However, this value includes naphthalene (2-ring), substituted naphthalenes and above, and therefore cannot be compared directly with the American Petroleum Institute cut-offs.

December 2004 Oil Mist Monitoring Protocol Page A- iii


Non Aqueoous (Oil Based) cont’s

Mineral oils reportedly contain less benzene, ethylbenzene and phenols than diesel. Compared with crude oil, diesel and mineral oil have a much narrower molecular weight range of saturated and aromatic hydrocarbons (2).

Water Based The liquid or continuous phase of the mud is fresh water or seawater. The other main ingredients include barite, clay, lignosulfonate, lignite, and caustic. Small concentrations of oil based lubricants and diesel fuel are normally present along with several other additives (2).

Synthetic The liquid continuous phase of the mud is composed of a synthetic organic ester, ether, acetyl or olefin. Olefins are hydrocarbons containing one or more double bonds. In drilling muds the hydrocarbons range from C15 to C30. Approximately 30% to 90% of the drilling muds are composed of the synthetic compounds by volume, or 20% to 40% by weight. Other additives are similar to water and mineral oil based drilling muds. (2).

Frac Oil A variety of frac fluids are available on the market. Composition varies between products, often being primarily stabilized gas condensate fractions, although at least one light crude oil is also used as a frac oil. Commonly the carbon range is C10-20.

One source reports a frac oil composition as >70% aromatic and paraffinic hydrocarbons (by volume), <15% toluene, <12% xylenes and up to 1.5% benzene. The total aromatic fraction was reported to be approximately 22 mol%. Napthalene was reported to make up 13 mol %. This frac oil was reported as having a flash point of 19˚C, a lower explosive limit of 0.87% (8700 ppm) and a vapour pressure of 3.3 kPa at 37.8˚C (12).

The total polycyclic aromatic hydrocarbon contents of three frac fluids reported in the draft Industry Recommended Practice 14.2 produced by the Drilling and Completions Committee of the Canadian Association of Petroleum Producers were 0.3 to 2.2% by weight, the highest concentration being recorded in a fluid sample during flowback (after mixing downhole).

December 2004 Oil Mist Monitoring Protocol Page A- iv


Mineral Oil Mildly Refined Mineral oils are prepared from naturally occurring crude petroleum oils. The crude oil is distilled normally at atmospheric pressure and then under high vacuum to give vacuum distillates and residual fractions that can be further refined to mineral base oils. The chemical composition of the mineral base oil produced depends both on the original crude oil from which it was refined as well as the exact process used during refining (10,20,21).

Severely Refined

After severe refining the differences due to the crude oil source are less apparent in the mineral oil (21).

Lubricants Lubricating oils are made from crude oil high-boiling residual stocks (2).

Lubricant based oils are reported to be composed of a complex mixture of straight and branched chained paraffins, cycloparaffins and aromatic hydrocarbons having carbons numbers of 15 or more and boiling points in the range of 300°C to 600°C (10). According to Skriftserie (1982), typical lubricating oils are composed of 68% aliphatic hydrocarbons, 30% aromatics and 2% polar substances. The relative proportions reflect the function of the lubricant (23).

Most lubricants are composed of mineral oils (base oils and derived products) (17,21)

CONCAWE classified lubricant oils into seven categories:

1 – Lubricants without additives produced from highly refined mineral oils

2 – Lubricants made from highly refined mineral oils with additives

3 – Lubricants with or without additives produced from base oils that have been mildly refined and contain concentrations of polycyclic aromatic hydrocarbons above levels normally achieved using solvent refining. These represent a minority of the market.

4 – Lubricants containing a significant portion of light petroleum distillates (white spirit, kerosene) or other volatile solvents.

5 – Water soluble oil emulsions.

6 – Lubricants composed of more than 50% synthetic base oils with or without additives.

7 – Solid or semi-solid materials such as lubricating greases and compounds (21).

December 2004 Oil Mist Monitoring Protocol Page A- v


Lubricants cont’s

Re-refined Oils May contain significant levels of polycyclic aromatic hydrocarbons and polychlorinated biphenyls (24).

Used Lubricants May be a mixture of a variety of lubricants. May be contaminated with a variety of products including polycyclic aromatic hydrocarbons, microbiological agents, and swarf (metals chips). In addition, nitrosamines and oxidation decomposition products may form in lubricating oils over time and be present in higher concentrations in used lubricants (21).

Diluted Lubricants primarily composed of mineral oil diluted in order to obtain a lower viscosity. Additive used to dilute the mineral oil include middle distillate products such as kerosene, gas oil, white spirit and non-flammable hydrocarbon solvents (21).

Metal Working Fluids: (also called Cutting Fluids, Machining Fluids, Metal Working Coolants)

Straight Straight metal working fluids are normally composed of one or more severely refined mineral oils together with extreme pressure additives, odourants, anti-mist compounds and anti-corrosion additives (1).

Composed of paraffinic or napthalenic oil 60% – 100%. Sometimes blended with vegetable or animal oils. Extreme pressure additives include sulphurized fats, chlorinated wax, and sulphochlorinated fats in small quantities (24).

Soluble Soluble metal working fluids are composed of an emulsion of mineral and fatty oils in water (25). Normally, the content of mineral oils and additives in soluble metal working fluids is less than 10% (11).

Synthetic Emulsion of organic compounds and inorganic salts in water (25).

Normally composed of hydrocarbons (poly-alpha olefins, poly-isobutenes, and alkylated aromatics), organic acid esters, phosphate esters, silicones, silicate esters, halogenated hydrocarbons and polyglycols (21).

December 2004 Oil Mist Monitoring Protocol Page A- vi


Metal Working Fluids: cont’s

Semi-synthetic Semi-synthetic metal working fluids are composed of an emulsion of mineral oil and water with synthetic additives (25).

Semi-synthetic metal working fluids are normally composed of 5% to 30% straight mineral oils, corrosion inhibitors, anionic and non-ionic surfactants, blending agents, biocides, water conditioners to prevent microbial growth, antifoaming agents and dyes (24).

Greases and Other Products

Greases normally consist of a base oil (mineral oil or synthetic oil) mixed with a dispersed solid thickener. The thickener, usually up to 25%, is most often soap but can also be inorganic clays, carbon black, bitumens, waxes and substituted ureas. Additives similar to those used in other lubricants may also be present (21).

Appendix B Health Effects of Oils

December 2004 Oil Mist Monitoring Protocol Page B- i

Oil Type Health Effects

Crude Oil Reported to be capable of causing slight eye irritation. Prolonged and repeated skin contact can cause dermatitis, folliculitis or oil acne. Inhalation of vapours or fumes can cause respiratory and nasal irritation. Inadvertent aspiration of the liquid of the light hydrocarbon fraction into the lungs can produce chemical pneumonitis, pulmonary edema, or hemorrhaging which can be fatal. Reported to be carcinogenic in humans. Pre-existing skin and respiratory disorders may be aggravated by exposure to crude oil (26).

May contain significant quantities of hydrogen sulphide gas. Sweet crude normally contains <500 ppm sulphur, while sour crudes may contain much higher concentrations ranging from 500 – 70,000 ppm. Exposure to 10 ppm may cause eye and upper respiratory tract irritation. Prolonged exposure to 50 – 100 ppm can produce significant eye and respiratory tract irritation. Exposure to 250 to 600 ppm for short periods can produce serious central nervous system effects, pulmonary edema and bronchial pneumonia. Concentrations > 1000 ppm will cause immediate unconsciousness and death through respiratory paralysis(26).

May contain significant quantities of benzene, hexane, toluene and xylenes (see below, health effects of individual volatile hydrocarbons) (26).

Non-Aqueous Drilling Fluids

The total volatility and the specific aromatic components of base oils in drilling fluids are the key factors impacting health hazards. The most prominent health effects reported from workplace exposure to non-aqueous drilling fluids are eye and respiratory tract irritation from the vapours. If the vapour concentrations are high enough, central nervous system depression is possible. See also below, health effects of individual volatile hydrocarbons (unpublished source).

Exposure to non-aqueous drilling fluid mists (either the liquid fluids or the less volatile synthetic fluids) can result in lung deposition and possible lung tissue damage. However, the skin and/or lung irritation from non-aqueous drilling fluids may be significantly impacted by the presence of various additives. Some additives are regarded as sensitizers. Very few reports of sensitization to non-aqueous drilling fluids are reported in the literature. However, according to one publication, polyamine sensitization in workers and “white spirit” sensitization of workers is possible (unpublished source).

December 2004 Oil Mist Monitoring Protocol Page B- ii


Non-Aqueous Drilling Fluids cont’s

The American Petroleum Institute considers oils containing less than 1% 3 – 7 ring or less than 0.1% 4 – 6 ring polycyclic aromatic hydrocarbons. to have a low likelihood of being carcinogenic.

Other health effects of non-aqueous drilling fluids include dermal irritation and contact dermatitis following prolonged exposure and/or repeated skin contact. These effects may arise from caustic contamination of the drilling fluids (unpublished source).

Frac Fluids27 General Health effects are likely to be variable depending on the composition of the fluid. However, as with vapours from condensates, diesel and drilling fluids, prominent short-term health effects are expected to be eye and respiratory tract irritation, and central nervous system depression (narcosis), with symptoms including dizziness, drowsiness, headache and nausea. Effects from mist are likely to include lung irritation, and possibly asthmatic effects.

Other health effects may be associated with individual hydrocarbon components. See also below, health effects of individual volatile hydrocarbons.

Mineral Oil Unspecified Light petroleum distillate vapours, such as kerosene, gas oil or solvents, may cause mild respiratory irritation. Inhalation of oil mist for short periods may cause irritation of the upper respiratory tract. Prolonged and repeated exposure to high concentrations may lead to the formation of lung fibrosis (21,23).

Inhalation of large amounts of oil mist can result in lipid pneumonia and increased lung markings (23).

Oil vapour is probably tolerated at concentrations of 500 to 1000 ppm (11)

Mineral oils have a low order of acute oral toxicity. Absorption in the digestive tract is minimal. Accident ingestion results in nausea, vomiting and diarrhea. Vomiting of low viscosity mineral oils can result in aspiration of the product into the lungs resulting in chemical pneumonitis (21).

Mineral oils have a low percutaneous toxicity. Application of mineral oils to the skin causes mild to moderate skin irritation in animals. Repeat exposure may cause defatting of the skin leading to irritation. Skin rashes or oil acne may occur following repeated and prolonged exposure (21).

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Mineral Oil cont’s

Unspecified cont’s

Mineral oil is non-irritating to the eyes of animals. Reported eye exposure may lead to irritation (21). Oil mist frequently irritates the eyes (23).

Exposure to oil can cause contact eczema, oil acne (23).

Mildly Refined The International Agency for Research on Cancer has reported that there is sufficient evidence of carcinogencity in experimental animals for several types of oil mists including vacuum distillates, mildly solvent refined, mildly hydrotreated, mildly acid treated and aromatic distillate extracts (10).

The International Agency for Research on Cancer, after reviewing the available information concluded that there is sufficient evidence from human studies that untreated or mildly treated mineral oils are carcinogenic (10).

Poorly refined mineral oils derived from petroleum are reported to be capable of inducing skin and scrotal cancers after prolonged, repeated and heavy skin contact (10).

Severely Refined

Respiratory tract and eye irritation (10,9).

At higher concentrations chemical pneumonitis, lipid pneumonia and an increased prevalence of basal lung fibrosis (10).

No evidence or insufficient evidence of carcinogenicity in experimental animals were reported for severely solvent refined, severely hydrotreated, severely acid treated and white oils (10).

The International Agency for Research on Cancer, after reviewing the available information concluded that there is insufficient evidence of carcinogenicity for highly refined mineral oils (10).

Mineral Oil cont’s

Diluted Inhalation hazard of diluted mineral oils is essentially that of the compound used to dilute the oil (21).

In animal studies, diluted mineral oils with a viscosity below 7cSt at 40°C were found to be hazardous if aspirated following ingestion. Aspiration resulted in severe lung damage and fatalities. Diluents with viscosities up to 15 cSt at 40°C may be fatal in animals. Diluents with greater viscosities present less of a hazard, resulting in localized ling tissue reactions only (21).

December 2004 Oil Mist Monitoring Protocol Page B- iv


Metal Working Fluids: (also called Cutting Fluids, Machining Fluids, Metal Working Coolants)

Not specified Symptoms reported in association with exposure to metal working fluids include cough, phlegm, dyspnea and diseases such as bronchitis and hypersensitivity pneumonitis which may lead to asthma (28).

Dermatitis, occupational asthma and allergic alveolitis (9).

Dermatitis caused by primary or direct skin irritation is the most prevalent health effect of exposure to metal working fluids. Allergic dermatitis and sensitization may occur as a result of one or more additives (24).

Reported to be associated with throat, pancreas, rectum and prostate cancers as well as breathing problems and respiratory illnesses (29).

Straight Acute inflammation of the lungs (lipid pneumonitis) and asthma (25).

Oil acne and folliculitis are the most common skin conditions reported for straight oils (24).

Light oils can defat the skin and denature membrane proteins. Symptoms characterized by redness, swelling and occasionally pustules. Irritant action decreases as the boiling point of the oil increases. Oils with a boiling point less than 600°C exhibit some irritant activity (24).

Chemical additives and contaminants may increase carcinogenicity of metal working fluids, cause irritation of the respiratory tract, cause respiratory or dermal sensitization (24,25).

Biological contaminants may cause respiratory symptoms and changes in lung function (25).

Metal Working Fluids: cont’s

Soluble The concentrate and the diluted emulsion may be irritating to the skin, eyes and respiratory tract. Microbiological exposure concerns have also been raised (21).

Non-allergenic contact eczema normally appears on the hands in connection with wet work using emulsified cutting oils. Allergic contact eczema is not common and commonly results from exposure to additives (23).

Health effects associated with water –mixed metal working fluids include irritation of the upper respiratory tract, occupational asthma, chronic inflammatory reaction of the lungs and a form of pulmonary fibrosis. A recent survey in the United Kingdon suggests that 6% – 7% of occupational asthma may be due to water-mixed metal working fluids (30)

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Synthetic Most synthetic based oils have a low order of acute toxicity and are only slightly or moderately irritating to the eyes and skin. Prolonged and repeated contact may result in dermatitis (21).

Consideration of all of the different compounds used in synthetic metal working fluids and their health effects is beyond the scope of this report, however, it is reported that these compounds do not pose a significant additional health hazard compared with straight mineral oils (21).

Synthetic coolants, which do not contain mineral oil, present similar health hazards to mineral oil based soluble oils (21).

Semi-synthetic Semi-synthetic coolants, which contain a small amount of mineral oil, present similar health hazards to mineral oil based soluble oils (21).

Greases and Other Products

The health effects of grease and other products are reported to be similar to mineral oils or synthetic oils. Products containing bitumens may present a carginogenic risk (21).

Re-refined Oils Polychlorinated biphenyls can cause chloracne, characterized by comedomes and yellowish cysts. Uncommon in industrial workplaces today (24).

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Volatile Hydrocarbons (27)

Benzene Long term exposure to benzene is thought to be associated with an increased risk of aplastic anaemia (a severe and sometimes fatal form of anaemia) and leukaemia. There is still uncertainty regarding both the dose rate (i.e. exposure concentration) and the cumulative dose (average dose rate x number of years exposed, expressed as mg/m3-years), above which an excess risk of leukaemia exists. Excess leukaemia risk has only been shown at cumulative doses of 33 mg/m3-years or more (e.g. 1.67 mg/m3 as an average over 20 years). Above this cumulative dose, the leukaemia risk appears to rise at an accelerating rate. Short term exposure to benzene appears to be an important risk factor. Evidence suggests that excess risk of leukaemia only occurs where peak exposures have exceeded 60 mg/m3. At progressively higher peak exposures the risk increases markedly. This may be the reason for the accelerating risk at cumulative doses above 33 mg/m3-years, since in the higher cumulative dose ranges, higher peak exposures would also be expected.

Short-term exposure to much higher airborne concentrations of benzene can also cause narcosis (see explanation under the health effects of other hydrocarbons below). Contact of the skin with liquid benzene can cause absorption of benzene into the body, with the same health effects as those caused by inhalation. Repeated skin contact may cause skin rash (dermatitis).

Toluene Short term exposure to toluene can cause mild drowsiness and headache at 50 ppm. Increasing concentrations can cause fatigue, dizziness, giddiness, numbness and nausea. Eye, nose and throat irritation are reported at 50 ppm (about 190 mg/m3) and above. High long-term exposure may cause nervous system (including memory loss and sleep disturbances), liver, and kidney effects (based on animal experiments). Toluene is not considered to be a mutagen or reproductive toxin. The liquid is absorbed through the skin slowly, and can cause skin irritation, defatting and dermatitis with repeated contact.

Ethylbenzene Short term exposure to ethyl benzene can cause mild vertigo, drowsiness, headache and other symptoms of narcosis at 100 ppm. Eye, nose and throat irritation are reported at 200 ppm (about 870 mg/m3) and above. High long-term exposure may cause nervous system effects (including memory loss and sleep disturbances), liver, kidney, and possibly blood or testicular effects (based on animal experiments). The ACGIH has recently proposed classifying this material as an animal carcinogen with unknown relevance to humans. Ethylbenzene is not considered to be a mutagen or reproductive toxin. The liquid is absorbed through the skin to some extent, and can cause skin irritation, defatting and dermatitis with repeated contact.

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Volatile Hydrocarbons cont’s

Xylenes Short term exposure to xylenes can cause dizziness, headache and other symptoms of narcosis. These are tolerable at 100 ppm (434 mg/m3), but become objectionable at higher concentrations. Eye, nose and throat irritation are reported at 200 ppm (about 870 mg/m3) and above. Neurobehavioural effects, such as impaired short-term memory, reaction time and balance have been reported in humans at 65-400 ppm. Higher exposures can cause nausea and vomiting. High long-term exposure may cause nervous system effects (including memory loss, fatigue, headaches, depression and sleep disturbances). Xylenes are not considered to be mutagens or reproductive toxins. However, there is some evidence from animal experiments of teratogenicity (harmful effects to the developing fetus). The liquid is absorbed through the skin to some extent, and can cause skin irritation, defatting and dermatitis with repeated contact.

Trimethyl benzene

Although direct evidence is limited, short term exposure to trimethyl benzenes probably cause dizziness, drowsiness, headache and other symptoms of narcosis, as well as eye, nose and throat irritation. Long term exposure may be associated with neurobehavioural effects (such as nervousness, tension and anxiety) and asthmatic bronchitis. There is also some evidence of blood effects, such as anaemia and effects on coagulation, although these effects may have been caused by benzene contamination.

n-Hexane Long term n-hexane exposure to several hundred mg/m3 is associated with peripheral neuropathy; that is, damage to the nerves in the arms and legs. Repeated skin contact with the liquid may cause skin rash (dermatitis). At high airborne concentrations n-hexane can also cause narcosis (see explanation under the health effects of other hydrocarbons).

Appendix C Exposure Standards and Guidelines

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Page C- i

Table 5-1 Oil Mist Exposure Standards and Guidelines

Jurisdiction and Regulator

Description Type of Exposure Standard or Guideline

Exposure Standard or Guideline

(mg/m3) Comments

Alberta Workplace Health and Safety – Chemical Hazard Regulation (31)

Oil Mist Mineral 8-Hour Occupational Exposure Limit

5 –

15-Minute Occupational Exposure Limit

10 –

British Columbia Workers’ Compensation Board – Occupational Health and Safety Regulation (32)

Oil Mist, Mineral, Mildly Refined

8-Hour Exposure Limit 0.2 K1 (confirmed human carcinogen), A (As low as reasonably achievable). Includes untreated oils, aromatic distillate extracts, as well as those oils that have been mildly solvent refined, mildly hydrotreated, mildly acid treated or catalytically cracked.

Oil Mist, Mineral, Severely Refined

8-Hour Exposure Limit 1 Includes white oils, as well as those oils that have been severely solvent refined, severely hydrotreated, or severely acid treated.

Saskatchewan – Saskatchewan Labour – Occupational Health and Safety Regulations (33)

Oil Mist, Mineral Severely Refined

8-Hour Workplace Contaminant Limits

5 –

15-Minute Workplace Contaminant Limits

10 –


Page C- ii




(mg/m3) Comments

Northwest Territories – General Safety Regulations (34)

Oil Mist, Mineral 8-Hour Occupational Exposure Limit

5 –

15-Minute Occupational Exposure Limit

10 –

Federal – Canadian Occupational Health and Safety Regulations (35)

Oil Mist, Mineral Time Weighted Average

5 Refers to the American Conference of Governmental Industrial Hygienists Threshold Limit Value and Biological Exposure Indices, dated 1994 – 1995, as amended from time to time

Short Term Exposure Limit

10

Federal – Oil and Gas Occupational Safety and Health Regulations (36)

Oil Mist, Mineral Time Weighted Average

5 Refers to the American Conference of Governmental Industrial Hygienists in its publication entitled Threshold Limit Values and Biological Exposure Indices for 1986-1987.

Short Term Exposure Limit

10

Occupational Safety and Health Administration (OSHA) (37)

Oil mist, mineral 8-Hour Permissible Exposure Limit

5 –


Page C- iii




(mg/m3) Comments

National Institute for Occupational Safety and Health (NIOSH) (38)

Oil mist, mineral Time Weighted Average Recommended Exposure Limit

5 –

Short Term Exposure Limit – Recommended Exposure Limit

10

National Institute for Occupational Safety and Health (NIOSH) (15)

Metal Working Fluids

Time Weighted Average (Thoracic)

0.4 Recommended Standard

American Conference of Governmental Industrial Hygienists (ACGIH) (39)

Oil mist, mineral Time Weighted Average Recommended Exposure Limit

5 Sampled by a method that does not collect vapour phase.

Note: Notice of intended change for Oil Mist Mineral to reduce Time Weighted Average to 0.2 mg/m3 based on respiratory effects. Mildly refined oil is listed as a suspected human carcinogen (A2). Highly refined oils are listed as not classifiable as a human carcinogen (A4). This category includes materials that could be carcinogenic to humans but which cannot be classified conclusively because of a lack of data.

Short Term Exposure Limit – Recommended Exposure Limit

10

mg/m3 – milligrams of contaminant per cubic metre of air.

Appendix D Sample Collection and Analytical Methods

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Table 6-1 Validated Oil Mist Sampling Methods

Description Method

Organization: Workers Compensation Board of British Columbia

National Institute for Occupational Safety and Health

Occupational Safety and Health Administration

Method Name: Oil Mist (Mineral) In Air Oil Mist, Mineral Oil Mist in Workplace Atmospheres

Method Number: 3201 5026 ID-128

Method Date: January 2002 May 1996 Not specified

Applicable Oils: Not specified Airborne mists of white mineral oil, or the following water-insoluble petroleum based cutting oils: cable oil, cutting oil, drawing oil, engine oil, heat-treating oils, hydraulic oils, machine oil, transformer oil. Applicable for trichlorotrifluoro-ethane soluble mineral oil mists.

Method is adequate for many aromatic oils including:

Petroleum – aliphatic or wax base, aromatic or asphalt base and mixed base

Petroleum derived – lubricants (engine oil, machine oil, cutting oil) and medicinal

Vegetable oils, animal oils, essential oils and edible oils.

Not Applicable Oils: Not specified Semi-synthetic or synthetic cutting fluids.

Not specified

Sample Collection

Collection Media: 37 mm, 5.0 µm pore size, polyvinyl chloride filter

37 mm, 0.8 µm mixed cellulose esterase, 5 µm polyvinyl chloride, 2 µm glass fibre or polytetrafluoroethylene filter

37 mm, 5 µm pore size, polyvinyl chloride filter

Sampling Method: Open face cassette Not specified Not specified

Flow Rate: 1 – 2 L/min 1 – 3 L/min 1 – 2 L/min

Recommended Volume: 200 L 20 L (at 5 mg/m3) – 500 L 150 L

December 2004 Oil Mist Monitoring Protocol Page D- ii

Range: 0.50 - 10 mg/m3 for 200 L sample 2.5 – 11.7 mg/m3 5 – 500 µg

Accuracy: To be determined +/- 11.8% Unknown

Precision: Not specified 0.05 Unknown

Quality Control: One blank for every nine samples Two blanks per set One blank per set

Sample Analysis

General Method: Gravimetric, followed by infrared spectrophotometry analysis

Infrared spectrophotometry analysis

Gravimetric, followed by fluorescence spectrophotometry

Critical Details: Pre-weigh filter.

Dessicate filter for 16 hours prior to post weighing.

Extract oil from filter using 1,1,2-trichlorotrifluoroethane (Freon 113)

Quantify oil mist by comparison of sample infrared absorption at approximately 2940 cm-1 to a series of standards prepared from a representative bulk sample of the oil.

Extract with carbon tetrachloride

Quantify oil mist by comparison of sample infrared absorption between 2700 to 3200 cm-1 to a series of standards prepared from a representative bulk sample of the oil.

Pre-weigh filter.

Post-weigh filter. If concentration less than 5 mg/m3 no further analysis required.

If greater than 5 mg/m3, analysis by fluorescence spectrophotometry required.

Dissolve oil from filters using chloroform.

Quantify oil mist by comparison of sample fluoresence to a series of standards prepared from a representative bulk oil sample.

Limit of Detection: 100 – 2000 µg/sample 0.1 – 2.5 mg/sample 15 g/ml

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Additional Comments

Interference Reported: Positive interference from compounds with absorption around 3000 cm-1.

Any aerosol which absorbs infrared radiation near 2950 cm-1 such as tobacco smoke.

Highly fluorescent compounds if they are soluble in chloroform.

Advantages Reported: Simple, specific and sensitive. None specified Sampling involves no liquids.

Desorption and preparation of samples for analysis involve simple procedures and instrumentation.

The analytical method is not sophisticated.

Time period between absorption and emission of energy is extremely short (10-8 to 10-3 seconds.

Disadvantages Reported: Representative bulk sample is required. Cannot quantify the amount of oil present without a bulk sample, only confirm the presence of oil mist.

Oil mist and particulate can stick to filter cassette housing.

Representative bulk sample required for analysis.

A bulk oil samples must be submitted that is identical to the oil in the samples.

Not all oils fluoresce. Only aromatic oils respond well to fluorescence analysis.

December 2004 Oil Mist Monitoring Protocol Page D- iv

Table 6-2 Alternate Oil Mist Sampling Methods

Description Method

Organization: ASTM International National Institute of Occupational Safety and Health (NIOSH)

EnviroTest Laboratories

Method Name: Provisional Standard Test Method for Metal Working Fluid Aerosol in Workplace Atmospheres

Not Applicable Oil Mist In Air (Modified Version of NIOSH Method 5026)

Method Number: PS 42-97 (withdrawn in 1998) Not applicable SOP# 3.01

Method Date: 1997 1998 (Criteria for a Recommended Standard: Occupational Exposure to Metal Working Fluids)

July 7, 2003

Applicable Oils: Metal working fluid oils, including straight oils, which contain no water, soluble oils

Metal working fluids including straight oils, , soluble (emulsifiable oil), semisynthetic oils, and synthetic oils

Hydrocarbon based oil mist

Not Applicable Oils: Not specified Not specified Non-hydrocarbon based metal working fluids or other oils

Sample Collection

Collection Media: 37 mm, 2 µm pore size, polytetrafluoroethylene filter

37 mm, 2 µm pore size, polytetrafluoroethylene filter with or without thoracic cyclone

37 mm, 2 µm pore size, polytetrafluoroethylene filter, with o-ring (no support pad)

Sampling Method: Closed faced sampling Thoracic fraction or total particulate closed face sampling

Not specified

Flow Rate: 2 L/min 1.6 L/min if using thoracic cyclone specified.

2 L/min for total particulate sampler.

1 – 3 L/min

Recommended Volume: Not specified Maximum of 1000 L 20 (at 5 mg/m3) – 500 L

December 2004 Oil Mist Monitoring Protocol Page D- v

Range: 0.05 – 5 mg/sample 0.2 – 5 mg/m3 for full shift sample

Not specified 2.5 – 11.7 mg/m3

Accuracy: Not determined at this time. Not specified +/- 11.8%

Precision: NIOSH Method reports a coefficient of variation of 0.026. Full validation of this method pending.

Not specified, however, comment that addition of an extraction method would decrease precision.

0.05

Bias NIOSH Method 0500 reports a bias of 0.01%. Full validation of this method pending.

Not determined. Expect less bias than total particulate sampling method, more bias than respirable sampling methods. Bias effected by particle size, external air velocity, orientation of filter cassette, filter cassette design, and evaporative losses of volatile components effect bias.

Not specified

Quality Control: Submit three field blanks per sample day or 10% of samples collected.

Not specified. Two blanks per set

Sample Analysis

General Method: Gravimetric extraction Gravimetric analysis Solvent extraction and analysis by GC/FID

Critical Details: Desiccate filters for minimum of eight hours and then pre-weigh.

Clean exterior of cassette, remove filter, desiccate for minimum of eight hours and then post-weigh.

Collect sample in accordance with NIOSH Method 0500 (Particulates Not Otherwise Regulated). Have the option of using a thoracic sampler or closed faces sampling cassette.

Collect samples in accordance with NIOSH Method 5026 using a polytetrafluoroethylene filter with an o-ring instead of a back-up support pad.

December 2004 Oil Mist Monitoring Protocol Page D- vi

Critical Details: cont’s

Extract metal working fluid from filter with equal volumes of dichloromethane (non-polar), methanol (polar), toluene (non-polar).

Equilibriate filter for a minimum of two hours, post-weigh. Determine concentration by dividing the mass difference between the two post-weights by the volume of air collected.

Analyze samples gravimetrically.

If using closed face total particulate sampling method instead of thoracic sampler, divide the mass detected by 1.25 to obtain approximate thoracic fraction of particulate.

Results to be compared to Recommended Exposure Limit of 0.4 mg/m3 for metal working fluids proposed.

Extract the oils mist using carbon disulphide or suitable solvent such as benzene, toluene or carbon tetrachloride. Sonicate for 15 minutes and then filter to remove particulate co-contaminants.

Analyze using high performance gas chromatgraphy coupled to a flame ionization detector.

Integrate entire chromatographic “hump” resulting from the eluting oil.

Compare area of hump to total areas obtained from analysis of calibration standards (Motor Master 10w30 oil or client supplied oil sample) to obtain concentration of oil in extract. Multiply concentration in extract by final volume to obtain total oil mist aerosol.

Limit of Detection: <30 µg or <0.03 mg/m3 reported for NIOSH Method 0500 (not fully validated).

Similar to NIOSH Method 0500 anticipated if limited to gravimetric analysis.

100 µg total oil/filter

Limit of Quantification: <100 µg or <0.10 mg/m3 reported for NIOSH Method 0500 (not fully validated).

Similar to NIOSH Method 0500 anticipated if limited to gravimetric analysis.

Not reported

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Additional Comments

Interference Reported: Total particulate matter portion of test method is not specific and is subject to positive bias by other aerosol sources.

Non specific method, non-metal working fluid particulate not differentiated on filter.

Not reported – See NIOSH Method 5026

Advantages Reported: Extracting the soluble mass improves the specificity of this test method by eliminating insoluble background aerosol. Important for low exposure limits

Extraction solvents can be analyzed for specific components/compounds in metal working fluid.

Thoracic sampling method better associated with reported health effects than the total sampling method.

Disadvantages Reported: Non specified Method does not take into account evaporative losses of volatile components of metal working fluids.

December 2004 Oil Mist Monitoring Protocol Page D- viii

Table 6-2 Alternate Oil Mist Sampling Methods Continued

Description Method

Organization: ASTM International National Institute of Occupational Safety and Health (NIOSH)

Method Name: (Draft Method Under Consideration) Standard Test Method for Metal Working Fluid Aerosol in Workplace Atmospheres

Metal Working Fluids (MWF) all Categories

Method Number: Not specified (Advised will be Method D664903)

5524 (Draft)

Method Date: Not specified (Likely 2003) 2003

Applicable Oils: Metal working fluid oils, including straight oils, which contain no water, soluble oils

Metal working fluids including straight oils, , soluble (emulsifiable oil), semisynthetic oils, and synthetic oils

Not Applicable Oils: Insoluble metal working fluids Insoluble metal working fluids

Sample Collection

Collection Media: 37 mm, 2 µm pore size, polytetrafluoroethylene filter

37 mm, 2 µm pore size, polytetrafluoroethylene filter with or without thoracic cyclone

Sampling Method: Closed faced sampling Thoracic fraction or total particulate closed face sampling

Flow Rate: 2 L/min 1.6 L/min if using thoracic cyclone specified.

2 L/min for total particulate sampler.

Recommended Volume: Not specified Minimum of 1000 L

Range: 0.05 – 5 mg/sample 0.2 – 5 mg/m3 for full shift sample

0.05 – 0.09 mg/sample

Accuracy: Not determined at this time. Total weight 0.12, extracted weight 0.14

Precision: NIOSH Method reports a coefficient of variation of 0.026. Full validation of this method pending.

Overall precision – total weight 0.06, extracted weight 0.07

Total weight 0.04 (>0.2 mg/sample), and 0.05 (>0.2 mg/sample) weight for extracted.

December 2004 Oil Mist Monitoring Protocol Page D- ix

Bias NIOSH Method 0500 reports a bias of 0.01%. Full validation of this method pending.

Not specified

Quality Control: Submit three field blanks per sample day or 10% of samples collected.

At least five field blanks per sampling set.

Sample Analysis

General Method: Gravimetric extraction Gravimetric extraction

Critical Details: Desiccate filters for two hours. Equilibriate the filters for two-hours. Then pre-weigh the filters.

Following sample collection, refridgerate samples.

Clean exterior of cassette, remove filter, desiccate for no more than two-hours, then equilibriate for no more than two-hours and then post-weigh.

Equilibriate samples for one hour. Pre-weigh filters (note static charge can cause erroneous readings) and assemble cassette.

Collect sample (total or thoracic) using closed-faced cassette or cyclone.

Refridgerate samples upon completion of sample collection and analyze within two weeks.

Collect bulk sample of each metal working fluid for solubility test.

Extract metal working fluid from filter with equal volumes of dichloromethane (non-polar), methanol (polar), toluene (non-polar). Follow this with an extraction using a one-to-one blend of water and methanol. Repeat the extraction with the ternary solvent.

Equilibriate filter for a minimum of two-hours, post-weigh. Determine concentration by dividing the mass difference between the two post-weights by the volume of air collected.

Test solubility of fluids by mixing 50 µl of the fluids with 10 ml of the ternary solvents. If after shaking, the solution is clear, free of precipitates and phase separation the method can be used.

Open the plugs from the cassettes and allow them to equilibrate for no more than two hours in a dessicator. The remove the filter and post weigh the sample.

Extract the metal working fluid with equal volumes of dichloromethane (non-polar), methanol (polar), toluene (non-polar). Follow this with an extraction using a one-to-one blend of water and methonal. Repeat the extraction with the ternary solvents.

Equilibriate filter for a minimum of two-hours, post-weigh.

December 2004 Oil Mist Monitoring Protocol Page D- x

Limit of Detection: <30 µg or <0.03 mg/m3 reported for NIOSH Method 0500 (not fully validated).

Estimated as 0.03 mg/sample for total weight, 0.03 mg/sample weight for extractables

Limit of Quantification: <100 µg or <0.10 mg/m3 reported for NIOSH Method 0500 (not fully validated).

Not specified

Additional Comments

Interference Reported: Total particulate matter portion of test method is not specific and is subject to positive bias by other aerosol sources.

None specified, however, any material collected on the filet and soluble in the extraction solvents may bias results

Advantages Reported: Method provides the concentration of total particulate matter for comparison with historical databases.

Method extends the former sampling method by adding the extraction step which improves the specificity of this test method by eliminating insoluble background aerosol. Important for low exposure limits.

Extraction solvents can be analyzed for specific components/compounds in metal working fluid.

Can be used for a wide variety of metal working fluid types.

Disadvantages Reported: Method does not address differences between types of metal working fluids.

Test method does not identify or quantify any specific toxins contained in the workplace that can be related to metal working fluids.

Test method is subject to negative bias as semi-volatile compounds can be lost from the filter during sampling.

Any metal working fluid components that are insoluble will not be measured.

Method does not take into account evaporative losses of volatile components of metal working fluids.

Appendix E Summary of Sample Collection and Analytical Methods

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Table 8-1 Summary of Sampling and Analytical Methods

Sampling Method

Analytical Method

Issues of Concern Advantages Disadvantages

Filter Gravimetric Filter type, wicking, collection efficiency, evaporative losses, co-contaminants and lack of specificity of method, size fraction of concern, sensitivity.

Simple and cheap Co-contaminants (particulate and other hydrocarbon mists), loss of oil mist due to evaporation, not good for short term sampling

Filter Extraction and gravimetric analysis

Filter type, collection efficiency, filter degradation, extraction solvent choice, extraction efficiency, wicking, evaporative losses, co-contaminants and lack of specificity of method, size fraction of concern, sensitivity.

Gets rid of particulate co-contaminants

Co-contaminants (other hydrocarbon mists), loss of oil mist due to evaporation, not good for short term sampling

Filter Extraction and analysis by IR analysis

Filter type, collection efficiency, filter degradation, extraction solvent choice, extraction efficiency, wicking, evaporative losses, size fraction of concern, co-contaminants, sensitivity.

Gets rid of particulate co-contaminants and greater specificity

Other hydrocarbons may have similar IR spectrum absorption, loss of oil mist due to evaporation, not good for short term sampling, bulk sample of oil desirable

December 2004 Oil Mist Monitoring Protocol Page E- ii

Sampling Method

Analytical Method


Filter Extraction and analysis by UV analysis



Other hydrocarbons may have similar UV spectrum absorption, loss of oil mist due to evaporation, not good for short term sampling, bulk sample of oil desirable

Filter Extraction and fluorescence analysis



Other hydrocarbons may have fluoresce at similar wavelength, loss of oil mist due to evaporation, not good for short term sampling, bulk sample of oil desirable

Electrostatic precipitator

Gravimetric Efficiency, collection efficiency, availability, co-contaminants, evaporative losses, intrinsically safe

Higher collection efficiency, less evaporative losses

Not readily available on the market in personal sampling size, intrinsic safety potentially an issue.

Filter Flame or inductively coupled plasma atomic absorption spectrometry for marker compounds – zinc, sodium, potassium, and boron

Applicability to oil type, filter type, collection efficiency, wicking, extraction solvent choice, extraction efficiency, size fraction, sensitivity, specificity (alternative sources present).

Evaporative losses no longer an issue, can have reasonable specificity if other sources of markers can be eliminated, good sensitivity, good for mineral oils, soluble, semi-synthetic and synthetic metal working fluids.

Must have bulk sample of metal working fluid as purchased and from where sampled, not all metal working fluids contain zinc or boron, boron hard to get good sensitivity, sodium and potassium high background rates, may effect sensitivity

December 2004 Oil Mist Monitoring Protocol Page E- iii

Sampling Method

Analytical Method


Filter with charcoal or Tenax tube in series

Any of the filter methods above plus GC or GC/MS for vapour phase

Filter type, wicking, collection efficiency, lack of specificity of method, size fraction of concern, extraction solvent, extraction efficiency, specificity of method, complexity of analysis, cost, interpretation relative to regulations, sensitivity.

Collection all of the oil (vapour or mist), no evaporative losses

Not comparable to exposure guidelines, more expensive, not specific to hydrocarbons found in oils, will collect and analyze all hydrocarbons, need bulk sample to quantify

Real time aerosol monitor

Not applicable Size fraction, comparability with validated methods, interferences, sensitivity, calibration, degradation of signal and sensor from oil mist.

Real time data available.

Good for short term sampling scenarios

Calibration issues, specificity issues, interference from other aerosols and water vapour, oil can accumulate on bulb degrading response.


9 References

1 Telephone discussion with Larry Serbin, Manager, Industrial Hygiene Division,

Envirotest Laboratories, March 30, 2003

2 PEMEX, Diagnosis of the Environmental Effects Associated with the Petroleum

Industry in Región Sur of PEP, Final Report, 1999

3 United States Environmental Protection Agency, Longhorn Partners Pipeline

Environmental Impact Assessment, Volume 2, Appendix 6A Composition

of Crude Oil and Refined Oil Products, Online Source: www.epa.gov/

earth1r6/6en/xp/1ppapp6a.pdf, Printed July 31, 2003

4 KCPC Educational Research Web Site: 9.2.1 Composition of Crude Oil, Online

source: www.kcpc.usyd.edu.au/ discovery/9.2.1-

short/0.2.1_CrudeOil.html, Printed June 25, 2003

5 CONCAWE, Environmental Classification of Petroleum Substances, 1995,

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/7395a8-I_CONCAWE_Briefing3.pdf, Printed: June 24, 2003

6 International Agency for Research on Cancer (IARC), IARC Monographs

Programme on the Evaluation of Carcinogenic Risks in Humans, Diesel

Fuels, Marine diesel fuel (Group 2B), Distillate (light) diesel fuels

(Group 3), Online Source: www-cie.iarc.fr/htdocs/monographs/vol45/45-

05.htm, Printed July 30, 2003

7 American Conference of Governmental Industrial Hygienists, Rational for the

Threshold Limit Values and Biological Exposure Indices, Diesel

Fuel/Kerosene, draft 1999

8 Schulumberger, Oilfield Glossary, Online Source:

www.glossary.oilfield.slb.com/Display.cfm?Term=

water%2Dbase%20drilling%20fluid, Printed: July 30, 2003

9 A.T. Simpson, J.A. Groves, J. Unwin and M. Piney, Mineral Oil Metal Working

Fluids (MWFs) – Development of Practical Criteria for Mist Sampling,

Journal of American Occupational Hygiene, Volume 44, Number 3, Pages

165 – 172, 2000

10 American Conference of Governmental Industrial Hygienists, Rational for the

Threshold Limit Values and Biological Exposure Indices, Oil Mist,

Mineral, 2001

11 CONCAWE, Report No. 1/81, guidelines for the determination of atmospheric

concentrations of oil mists, Prepared by the Industrial Hygiene Subgroup

of CONCAWE’s Health Advisory Group, January 1981

12 Conoco Canada Limited, C2000 Frac Oil, Material Safety Data Sheet, Online

Source: http://lubes.conoco.com/activepdf/pdf/51GASC0021.pdf, Printed:

July 29, 2003


13 Chevron, Material Safety Data Sheet, Chevron LS Diesel 2, June 9, 2001,

Online source: library.cbest.chevron.com/lubes/chev.msdsv9.nsf, Printed

July 30, 2003

14 Phillips Petroleum Company, Material Safety Data Sheet Summary Sheet, No. 2

Diesel Fuel, January 1, 2002, Online Source:

www.petrocard.com/Products/MSDS-ULS.pdf, Printed July 30, 2003.

15 National Institute of Occupational Safety and Health, Criteria for a

Recommended Standard: Occupational Exposure to Metal Working

Fluids, January 1998

16 K.Svendsen, O.Bjorseth and E.Borrsen, Sampling Petroleum Oil Mist and

Vapour; Comparison of Methods, American Industrial Hygiene

Association Journal, Volume 57, Pages 537 – 541, 1996

17 E.Menichini, Sampling and Analytical Methods for Determining Oil Mist

Concentrations, Annals of Occupational Hygiene, Volume 30, Number 3,

Pages 335 – 348, 1986

18 Discussion with Mr. Otto Peter, Corporate Health and Safety Department,

General Motors, April 30, 2003.

19 N.A. Leidel, J.A. Lynch, and K.A. Busch, Occupational Exposure Sampling

Strategy Manual, US Department of Health, Education and Welfare,

NIOSH, Cincinnati, Ohio, January 1977

20 United States Department of Health and Human Services, Public Health

Service, National Toxicology Program, Tenth Report on Carcinogens,

Mineral Oils* (Untreated and Mildly Treated), Online Source

eph.niehs.nih.gov/roc/toc10.html, Printed July 2003

21 CONCAWE, Special Task Force PHH/STF-10, Health Aspects of Lubricants,

Report No. 5/87, CONCAWE, The Hague, 1987

22 Drilling and Completions Committee of the Canadian Association of Petroleum

Producers, Industry Recommended Practice 14.1, Calgary, Alberta, 2001

23 Arbete Och Hälsa, Vetenskaplig Skriftserie, Scientific Basis for Swedish

Occupational Standards II, Arbeter-Skyddsverket, 1982

24 C.R. Mackerer, Health Effects of Oil Mists: A Brief Review, Toxicology and

Industrial Health, Volume 5, Number 3, Pages, 429 – 440, 1989

25 S.R. Woskie, M.A. Virja, et. al., Exposure Assessment for a Field Investigation

of the Acute Respiratory Effects for Metal Working Fluids.1.Summary of

Findings, AIHA Journal, Volume 57, Pages 1154 – 1162, December 1996

26 Marathon Ashland Petroleum LLC, Material Safety Data Sheet, MAPLLC

Petroleum Crude Oil, Online Source:

www.mapl.com/msds/msds/110mar019.html, Printed June 25, 2003


27 Certified Industrial Hygiene Consulting Ltd., Ian P. Wheeler and Edward A.

Morgan, Report On Exposures To Volatile Hydrocarbons and Oil Mist

During Drilling Operations, Calgary, Alberta, 2001

28 M. Harper, Extracting Metalworking Fluid Aerosol Samples in Cassettes by

Provisional ASTM and NIOSH Methods, AIHA Journal, Volume 63,

Pages 488 – 492, July/August 2002

29 D.Leith, F.A. Leith, and M.G. Boundy, Laboratory Measurements of Oil Mist

Concentrations Using Filters and an Electrostatic Precipitator, AIHA

Journal, Volume 57, Pages, 1137 – 1141, December 1996

30 A.M. How and S.D. Bradley, Measurement of personal exposure to airborne

water-mix metalworking fluids, Health and Safety Laboratory, Sheffield

UK, Online Source: www.aiha.org/aihce01/handouts/ps604howe.pdf, June

2003

31 Alberta Workplace Health and Safety, Alberta Regulation, Occupational Health

and Safety Act, Chemical Hazards Regulation, November 2002

32 Workers’ Compensation Board Occupational Health and Safety Regulation, BC

Regulation 296/97, as amended by BC Regulation 185/99

33 Saskatchewan Labour, Occupational Health and Safety Regulations, 1996

34 Workers’ Compensation Board of Northwest Territories and Nunavut, Safety

Act, General Safety Regulations, RRNWT 1990, C. S-1

35 Human Resources Development Canada, Canada Labour Code Part II,

Canadian Occupational Health and Safety Regulations, Section

10.19(1)(a), Updated September 2002

36 Human Resources Development Canada, Canada Labour Code Part II, Oil and

Gas Occupational Safety and Health Regulations 1985, Section 11.23

(1)(a), Updated December 1996

37 US Department of Labour, Occupational Health and Safety Standards, Part

1910, Subpart Z, Toxic and Hazardous Substances, Table Z-1 Limits for

Air Contaminants 1910.1000, 1999

38 NIOSH Recommendations for Occupational Safety and Health, Compendium of

Policy Documents and Statements, DHHS (NIOSH) Publication No. 92-

100, NIOSH RELs and General Recommendations for Safety and Health,

1992

39 American Conference of Governmental Industrial Hygienists (ACGIH)

Worldwide, Threshold Limit Values for Chemical Substances and

Physical Agents and Biological Exposure Indices, 2003

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