HAZARDOUS LIGHTING

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Aspects of Hazardous Area LightingLight fittings for use in hazardous areas have the following characteristics. They are sealed to prevent the ingress of either the liquid or gas or dust. They have a lens for lamp protection made of a robust or impact resistant material of a greater strength than for a normal commercial fitting. They have a seal or machined face to ensure resistance to liquid, dust or gas, or to quench a flame path.

Light fittings have different grades of protection depending on their construction and intended purpose.

Some fittings are classified according to their IP International degrees of Protection rating as it is designated.

Where the first numeral indicates resistance to solids and the second to liquids, the Table indicates the actual values.

It can be seen that IP53 is probably the lowest rating that can be used in the presence of water, vapour, moisture or dust and corrosive vapours, the best rating for the same installation would normally be IP65 or IP66. Light fittings subject to high pressure hosing require even higher classification IP67.

What constitutes a hazardous area in some contexts it could be a badly lit step, however, we consider it to be an area in which a flammable material, gas or vapour is be mixed in the correct proportion with air and within this mixture if a spark or heat is present, it would be sufficient to ignite the mixture.

When Light fittings and other electrical apparatus are to be installed in a hazardous area it is essential that the decision maker takes measures to reduce the likelihood of an explosion by the correct selection of the equipment to be installed in that area.

As the gases and vapours liable to be present are rated according to ignition temperature, flash point and lower explosive limit, this information must be on hand when making your light fitting selection.

Gases also have a gas group classification, namely Group I, Group IIA, Group IIB and Group IIC, where Methane falls in the category Group I, while Hydrogen is a Group IIC gas, together with Acetylene.

At present, with the recent acceptance of IEC 79 specification, the industry is in the process of moving from a Divisional nomenclature to a rating where Zone 0, previously Division 0, is an area which is continuously explosive. And Zone 1, previously Division 1, is an area which is likely to be explosive under normal working conditions. Zone 2, previously Division 2, is normally explosive in unusual situations, such as a failed gland or joint which leaks or is damaged. The general classification of the area is then

Zone 1&2 for gases and vapours and volatile liquids present in the air

Zone 21 for combustible dusts, metallic and non-metallic and also fibres in suspension in the air

Zone 22 dust and easily combustible fibres, not normally in suspension in the air, but are present in sufficient quantities to produce a combustible mixture.

Various types of lighting equipment are available for installation in the various hazardous locations, some are locally manufactured while others are imported, mainly from Europe.

A common fault of the light fitting purchaser is the non-specification of the gland type required for the installation. This has to be compatible to the type of cable and the core diameters.

There are different glands available for steel armoured cable and for sheathed cables. Also cables should be of the flame retardant type if for exposed useage and if not sand covered.

Of the more common type of light fittings available for the Zone 1 situation are those designated and enclosed in

i) Flameproof or explosion proof Ex d housings.

ii) Increased Safety Ex e.

Although both are suitable for use in this type of atmosphere there is a world of difference in their construction format.

Hazardous Material

gas/vapour/dust

IGNITIONHAZARD

Air/Oxygen Supporter of Combustion

Source of Ignition

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HAZARDOUS LIGHTING

1. FLAMEPROOF F.L.P. of UK origin and Explosion proof Ex d of German origin have as a common feature, heavy cast components and very thick glass the manufacture of which is strictly specified and controlled.

Most flameproof housings are made of cast iron, phosphor bronze or brass, for underground use. Only for surface use can Aluminium Alloy be considered.

Lamp protection is usually by means of a glass dome, however recently polycarbonate is being allowed.

As can be seen from the materials used in construction, there is sufficient mechanical strength to withstand an explosion of the gas within the light fitting without damage and without the explosion being transmitted to the surrounding gas. The flanged joints are very accurately machined, where the width of the flange is determined by the volume and group of the enclosure. The glass is in turn cemented and clamped into position to ensure strength of the housing.

As the material of the body is metal, earth continuity is essential and the correct glanding must be strictly adhered to. Unused entries must be plugged. This seems an obvious statement but often during maintenance or installation small modifications can occur. The means of mounting is always external to the enclosure. The joint is lightly coated with a protective grease.

Electrical components are of normal construction as used in unprotected apparatus.

2. Increased Safety Ex e.

These light fittings are not generally used underground in the mines because of their much lighter construction. The materials used are normally glass-fibre-reinforced polyester, or aluminium alloy or glass and stainless steel. Special care is taken to ensure that there is absolutely no risk of producing electrical sparks, arcs or excessive temperature in normal operation. This is achieved through high quality type insulation, electrical connection without the possibility of loose terminations and special construction of low temperature control gear and lamps. It is not only the surface temperature in this type of fitting that is important but also that of each individual component. The international temperature rating table is given in Table 2.

Type Ex e glands are used and earth continuity is provided for when steel armoured cable is used. For flexible or sheathed cable Ex e compression glands are to be used.

The minimum required IP rating is IP 54 although most have a higher rating. Lamp protection is either by means of armoured plate glass, a very thick borosilicate glass dome, or a polycarbonate lens.

Markings for Zone 1 fittings are vitally important as these tell the type of light fitting ie. Exd or Exe, voltage, maximum wattage lamp,catalogue number. Most importantly the Test Authority is indicated. It is illegal to market a light fitting without a certificate. The inability of the vendor to supply this certificate probably means the goods are not in accordance with their claims and the onus rests with the purchaser to protect himself and his installation. Temperature limits are also indicated on the label so that the matching of ignition temperatures and light fitting limitations can be assessed for suitability.

If the light fittings are not switched external to the hazardous area, a flame proof isolating switch must be used which cuts both the live and neutral i.e. two pole.

A step down from Exd and Exe is Exn or commonly known as non-sparking, a term which describes the method of construction. These light fittings would be used in Zone 2 locations where the degree of hazard is lower. Basically of fibre-glass-reinforced polyester or polycarbonate design, they have slightly lower insulation and creepage distances than the Exe on lampholders and terminal blocks.

In each case the degree of protection of the housing or enclosure is indicated,

NOTE: Hazardous Area Certified products are approved on a country specific basis. Please contact Hella for details.

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2. Special Systems

No mention has been made of some of the exotic forms of protection which are available or light fittings such as those driven by compressed air and suitable for Zone 0 locations, as it is a special design and pressure positive, the labels reads Ex s. Other light fittings or components have the following designations:

Intrinsically Safe Exia or ib

Encapsulated Exm

Pressured or purged Exp

Sand filled Exq

Light fittings being only one of the electrical items used within the hazardous environment also need to be checked and serviced regularly and special care must be taken when relamping to see that machine faces are not corrosion pitted or gaskets damaged, that glands are still tight and not corroded and finally, that the sealing screws and devices are all tightly replaced and none missing.

IEC 79-14 of 1984 covers most of the pitfalls in the wiring of electrical apparatus for explosive gas atmospheres.

TABLE 1

INGRESS PROTECTION (IP) CODES

FIRST NUMERAL SECOND NUMERAL Protection against solid bodies Protection against liquid

0 NO PROTECTION 0 NO PROTECTION

1 OBJECTS GREATER THAN 50MM 1 VERTICALLY DRIPPING WATER

2 OBJECTS GREATER THAN 12MM 2 75 to 90- ANGLED DRIPPING WATER

3 OBJECTS GREATER THAN 2.5MM 3 SPRAYED WATER

4 OBJECTS GREATER THAN 1.0MM 4 SPLASHED WATER

5 DUST-PROTECTED 5 WATER JETS

6 DUST-TIGHT 6 HEAVY SEAS

7 EFFECTS OF IMMERSION

8 INDEFINITE IMMERSION

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Hazardous Area ApparatusZone 0, Zone 1 and Zone 2 Locations

GENERAL. Zone 0, Zone 1 and Zone 2 locations are those in which flammable gases or vapours are or may be present in the air in quantities sufficient to become hazardous.

Zone 0 Locations.

These are locations in which flammable gases or vapours are continuously present in concentrations within the lower and upper limits of flammability.

NOTE: Such a condition is rarely encountered and is limited mainly to confined spaces (such as the vapour space of closed process vessels, closed tanks and closed containers), although it may also occur in larger rooms, such as rooms in chemical plants. Even in such spaces it is possible that the gas-air or vapour-air mixture is normally outside the flammability range.

Zone 1 Locations.

These are locations

a) in which hazardous concentrations of flammable gases or vapours occur intermittently or periodically under normal operating conditions, or

b) in which hazardous concentrations of flammable gases or vapours may occur frequently because of repair or maintenance operations or leakage, or

c) in which breakdown or faulty operation of equipment or processes, which release dangerous concentrations of flammable gases or vapours, might also cause simultaneous failure of electrical equipment.

NOTE: This classification usually includes locations where volatile flammable liquids or liquified flammable gases are transferred from one container to another; interiors of spray booths and areas in the vicinity of spraying and painting operations where volatile flammable solvents are used; locations containing open tanks or vats of volatile flammable liquids; drying rooms or compartments for the evaporation of flammable solvents; locations containing fat or oil-extraction apparatus using volatile flammable solvents; portions of cleaning and drying plants where flammable liquids are used; gas generator rooms; inadequately ventilated pump rooms for flammable gases or for volatile flammable liquids and all other locations where hazardous concentrations of flammable vapours or gases may occur in the course of normal operations.

Zone 2 Locations.

These are locations in which operations concerned with flammable or explosive substances, gases, or vapours or volatile liquids are so well controlled that an explosive or ignitable concentration is only likely to occur under abnormal conditions.

NOTE 1: The following shall be regarded as the minimum requirements for a location to which this classification is applicable:

a) The area is so well ventilated that, if abnormal conditions arise, ignitable concentrations of the gas or vapour are rapidly dispersed and their possible contact with electrical equipment is of minimum duration.

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Zone 21 and Zone 22 LOCATIONS

GENERAL. Zone 21 & 22 locations are those which are hazardous because of the presence of combustible dust and fibres.

NOTE: Locations that house only plant and machinery that become non-operative if they lose their dust-tightness or if their internal pressure ceases to be below atmospheric pressure and locations where combustible dust is stored in dust-tight containers only need not be classified. The classification of locations where dust is not normally in suspension in the air, but where mechanical failure or abnormal operation of machinery or equipment might cause suspension of dust and might also provide a simultaneous source of ignition through failure of electrical equipment, operation of protective devices, etc., depends on the specific circumstances.

Zone 21 Locations.

These are locations

a) in which, under normal operating conditions, combustible dust or fibre is (or is likely to be) in suspension in the air in quantities sufficient to produce an explosive or ignitable mixture,

b) in which metallic dusts may be present.

NOTE: This classification usually includes, for example, rooms containing machines (such as grinders, pulverizers, cleaners, graders and scrapers that are not provided with suitable dust extraction or exhaust systems, open bins and hoppers, terminal points of open conveyors and spouts in grain processing plants, starch plants, sugar plants, malting plants, hay plants and coal plants); and all working areas where metallic dusts and powders are produced, processed, handled, packed, or stored (except when these are stored in sealed containers).

Zone 22 Locations.

These are locations in which combustible dust or fibre will not normally be in suspension in the air, or will not be likely to be thrown into suspension by the normal operation of equipment or apparatus, in quantities sufficient to produce an explosive or ignitable mixture, but where

a) deposits or accumulations of such dust may be enough to interfere with the safe dissipation of heat from electrical apparatus, or

b) deposits or accumulations of dust in, on, or in the vicinity of electrical apparatus might be ignited by arcs, sparks, or burning materials from such apparatus.

Flameproof Apparatus

Apparatus so enclosed that the enclosure will withstand, without injury, any explosion of the prescribed flammable gas or vapour that may occur within it under practical conditions of operation within the rating of the apparatus (and recognised overloads, if any, associated with the rating) and will prevent the transmission of flame such as will ignite the prescribed flammable gas or vapour which may be present in the surrounding atmosphere.

Explosion-Proof Apparatus Apparatus enclosed in a case that

a) is capable of withstanding an internal explosion of a specific gas or vapour,

b) is capable of preventing the ignition (by arcs, sparks, or explosions that occur inside the case) of a specific gas or vapour surrounding the enclosure, and

c) has not, when the apparatus is operating, an external surface temperature high enough to ignite a prescribed gas or vapour-air-mixture.

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NOTE: The German term explosions-geschtzt (frequently translated as explosion-proof) is used also to denote apparatus protected otherwise than by means of an explosion-proof case. Such other methods include those described in the code under the definitions of intrinsically safe apparatus, pressurised apparatus, and Type e apparatus.

Ex e Apparatus (Increased Safety Apparatus).

Apparatus in which special precautions have been taken to prevent sparking, arcing, and the occurrence of temperatures high enough to ignite a prescribed gas or vapour-air mixture.

Ex n Non-Sparking Apparatus.

Apparatus that in normal operation and in the absence of electrical or mechanical failure does not spark or arc or develop temperatures high enough to ignite a prescribed gas or vapour-air mixture.

Dust-ignition-Proof Apparatus.

Apparatus so enclosed as

a) to prevent the entry of enough dust to be ignited or to impair the performance of the apparatus, and

b) to prevent arcs, sparks, and heat, generated or liberated in the enclosure by other means, from igniting accumulations of a dust on the outside of the enclosure and atmospheric suspensions of a dust in the vicinity of the enclosure.

CLASSIFICATION OF HAZARDOUS LOCATIONS

GENERAL. The descriptions in this section are given in general terms only. In determining the classification of a location and its extent, cognisance should always be taken of the likelihood of explosive conditions arising, of the adequacy and reliability of ventilation, of the quantity and nature of flammable or explosive material that can possibly be released, of the detection and removal of flammable or explosive materials that are released, and of all other pertinent factors.

Piping without valves, checks, meters and similar devices would not normally be deemed to introduce a hazardous conditions even though used for flammable liquids or gases.

Flameproof ApparatusEnclosures are divided into the following main groupsGroup 1 for use underground in mines, i.e. for use in the presence of methane (fire damp)Group 2 for use above ground and subdivided according to their suitability for use in atmospheres

containing specific gases and vapours as shown in the following table.

Subgroup Gas/VapourIIA Industrial methane* Ethyl methyl ketone Ammonia methyl acetate Blastfurnace gas Ethyl acetate Carbon monoxide n-Propyl acetate Propane n-Butyl acetate Butane Amyl acetate Pentane Chloro-ethylene Hexane Methanol Heptane Ethanol iso-Octane iso-Butanol Decane n-Butanol Benzene Amyl alcohol Xylene Ethyl nitrite Cyclohexane AcetoneIIB Buta-1:3 diene Ethylone oxide Ethylene Coal gas (Town gas)** Diethyl ether Coke-oven gasIIC Hydrogen

* Industrial methane includes methane mixed with not more than 10% (v/v) of hydrogen.

** Town gas may contain not more than 57% (v/v) of hydrogen and not more than 16% (v/v) of carbon monoxide, the remainder being a mixture of paraffin hydrocarbons and inert gas.

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TEMPERATURE CLASSESGas GroupClassification 450 C - T1 300 C - T2 200 C - T3 135 C - T4 100 C - T5 85 C - T6

I Methane

IIA Ammonia Xylene Cyclohexane Heptane

Carbon Monoxide Acetone Diesel Hexane

Chlorobenzine Ethanol Aviation Fuel

Pentane Propane n-Propul Alcohol

Methanol Petrol

Ethylacetate

Benzene

Amylacetate

n-Butyl Alcohol

n- Butane

IIB Coal Gas Ethylene

Buta 1:3 Diene Diethyl Ether

IIC Hydrogen Acetylene Carbon Disulphide

TABLE 2

RATING BY TEMPERATURE 1 2 3 Temperature Limiting Gases and vapours class temperature against which protection C is afforded*

T1 450 Chlorobenzene, ammonia, carbon monoxide, coal gas, hydrogen, water gas

T2 300 Acetone, ethane, ethyl chloride, xylene, benzene (pure), methane, methanol, naphthalene, propane, toluene, ethyl acetate, ethanol, ethylene, cyclohexanone, isoamylacetate, 1.4 dioxan, n-butane, n-butylalcohol, acetic acid, buta-1.3-diene, vinyl acetate, ethyl benzene

T3 200 Acetylene, n-propylalcohol, petrol, crude oil, turpentine, cyclohexane T4 135 n-tetradecane, tetrahydrofuran, trichlorosilane, ethyl glycol, n-hexane, n-heptane, n-nonane acetaldehyde, ethyl ether

T5 100 No gas or vapour specified as yet

T6 85 Carbon disulphide

* Apparatus classified in a temperature class is deemed to be suitable for use in gases and vapours appropriate to that and all lower temperature classes. For instance, a lamp reaching a temperature of 130 C would be marked T4. That temperature would not ignite

the gases or vapours in the T4 row; neither would it ignite the gases or vapours in the T3, T2 or T1 rows. However, that temperature would ignite gases or vapours in the T5 or T6 rows, such as carbon disulphide.

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1. HydrocarbonsAlkanesMethaneEthanePropaneButanePentaneHexaneHeptaneOctaneNonaneDecaneCyclobutaneCyclopentaneCyclohexaneCycloheptaneMethylcyclobutaneMethylcyclopentaneMethylcyclohexaneDecahydronaphthalene(Dekalin)

AlkenesPropene (Propylene)Aromatic HydrocarbonsStyreneIsopropenylbenzene(Methyl Styrene)

BenzenoidsBezeneTolueneXyleneEthylbenzeneTrimethal benzeneNaphtaleneCumeneCymeneMixed HydrocarbonsMethane (industrial)TurpentinePetroleum NaphthaCoal Tar NaphthaPetroleum (includingmotor spirit)

Solvent or CleaningPetroleumHeating oilKeroseneDiesel OilMotor Benzole

2. CompoundsContaining OxygenOxides(Including Ethers)Carbon MonoxideDipropyl Ether

Alcohols and PhenolsMethanolEthanolPropanolButanolPentanolHexanolHeptanolOctanolNonanolCyclohexanolMethylcyclohexanolPhenolCresol4-Hydroxy-4-Methylpentan-2-one(Diacetone Alcohol)

AldehydesAcetaldehydeMetaldehyde

KetonesAcetoneButanone(Ethyl Methyl Ketone)Pentan-2-One(Propyl Methyl Ketone)Hexan-2-One(Butyl Methyl Ketone)Amyl Methyl KetonePentane-2, 4-Dione

(Acetylacetone)Cyclohexanone

EstersMethyl FormateEthyl FormateMethyl AcetateEthyl AcetatePropyl AcetateButyl AcetateAmyl AcetateMethyl MethacrylateEthyl MethacrylateVinyl AcetateEthyl Acetoacetate

AcidsAcetic Acid

3. CompoundsContainingHalogensCompounds withoutOxygenChloromethaneChloroethaneBromoethaneChloropropaneChlorobutaneBromobutaneDichloroethaneDichloropropaneChlorobenzeneBenzyl chlorideDichlorobenzeneAllyl chlorideDichloroethyleneChloroethylene(Vinyl Chloride)D,D,D-Trifluorotoluene(Benzotrifluoride)Dichloromethane(Methylene Chloride)

Compounds with OxygenAcetyl Chloride

Chloroethanol

4. CompoundsContaining SulphurEthanethiol(Ethylmercaptan)Propane-1-Thiol(Propylmercaptan)ThiopheneTetrahydrothiophene

5. CompoundsContaining NitrogenAmmoniaAcetonitrileEthyl NitriteNitromethaneNitroethane

AminesMethylamineDimethylamineTrimethlamineDiethylamineTriethylaminePropylamineButylamineCyclohexylamine2-Aminoethanol(Ethanolamine)2-DiethylaminoethanolDiaminoethaneAanilineNN-DimethylanilineAmphetamineToluidinePyridine

A More Detailed List Of CompoundsSubdivision A

Subdivision B

1. Hydrocarbons propine (allylene, methylacetylene) ethylene cyclopropane 1,2-butadiene

2. Compounds Containing Nitrogen acrylonitrile isopropyl nitrate hydrogen cyanide

3. Compounds Containing Oxygen dimethyl ether ethyl methylether diethyl ether dibutyl ether ethylene oxide (oxione) 1,2-epoxypropane (propylene oxide) 1,3-dioxolane 1,4-dioxan 1,3,5-trioxan butyl glycolate (hydroxyacetic acid, butyl ester) tetrahydrofurfuryl alcohol methyl acrylate ethyl acrylate furan crotonaldehyde acrylaldehyde (acrolein) tetrahydrofuran

4. Mixtures coke oven gas

5. Compounds Containing Halogens tetrafluoroethylene 1-chloro-2, 3-epoxypropane (epichlorohydrin)

1. hydrogen acetylene carbon disulphide ethyl nitrate

Subdivision C

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Chemical Material Investigated

Accumulator Acid Acetic Acid up to 5% Acetic Acid up to 15% Acetone Alcohol up to 30% Alcohol concentrate Ammonia 25% Aniline Aromatic Hydrocarbons Benzine Carbon Dioxide Carbon Monoxide Carbon Tetrachloride Caustic Soda 2% Caustic Soda 10% Chloroform Common Salt Crude Oil Diesel Oil Dioxane Ether Ethyl Acetate Glycerine Glycol Hydrobromic Acid Hydrocarbons Hydrochloric Acid 5% Hydrochloric Acid 30%

Chemical Material Investigated

Hydrochloric Acid 96% Hydrogen Peroxide over 40% Hydrogen Sulphide Ketones Lyso Metal Salts

and their aqueous solutions Methanol Methylene Chloride Milk of Lime Nitric Acid 5% Nitric Acid 30% Nitric Acid concentrate Petrol Petroleum Ether Phenol Pyridine Sea Water Soap Suds Soda Sulphuric Acid 5% Sulphuric Acid 30% Sulphuric Acid concentrate Sulphurous Acid 5% Synthetic detergent Turpentine Water up to 70 C Xylene

Aluminium

Fibreglass

Acrylic

Polycarbon

ate

StainlessSteel

Aluminium

Fibreglass

Acrylic

Polycarbon

ate

StainlessSteel

Tables for Chemical Resistance Ambienttemperature20C Resistant Resistantwithinlimits Notresistant Resistantwhensaturated,resistantwithinlimitswhensaturated.

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Tables for Chemical Resistance

Polycarbonate is soluble in a number of technical solvents. Good solvents include: methylene chloride, ethylene chloride, trichloroethane, tetrachloroethane, chloroform, m-cresol and pyridine.

Comparatively poor solvents for polycarbonate include: deoxane, tetrahydrofuran, cyclohexanone and dimethylformamide.

Examples of swelling agents are: benzene, chlorobenzene, tetralin, acetone, ethyl acetate, acetonitrile and carbon tetrachloride.

Polycarbonate is resistant to mineral acids, even in high concentrations, many organic acids, oxidising and reducing agents, neutral and acid salt solutions, many greases, waxes and oils, saturated, aliphatic and cycloaliphatic hydrocarbons and alcohols, with the exception of methyl alcohol.

Polycarbonate is chemically degraded by aqueous or alcoholic alkaline solutions, ammonia gas and its solutions and also by amines.

1. Chemicals= acetaldehyde+ acetic acid up to 10%= acetone= acrylonitrile= ammonia= ammonium hydroxide solution+ ammoniym sulphate, saturated solution in water= benzene= benzoic acid+ borax, saturated solution in water= bromine+ butylene glycol+ calcium hypochlorite+ carbon dioxide, moist= caustic potash= caustic soda+ chlorinated lime solution 2% in waterO chlorine gas, dry= chlorine gas, moist+ chromic acid, 20% in water+ coal gas= cresol= dibutyl phthalate (plasticiser)+ diethylene glycol= dioxane+ ethanol= ether+ ethyl alcohol 96% pure= ethylene chloride+ ethylene glycol+ formalin 10%O formic acid 30%+ glycol+ heptane= hydrochloric acid, conc.

+ hydrochloric acid 20%+ hydrogen sulphide+ ligroin (hydrocarbon mixture)+ methane= methanol= methylmethacrylate+ nitric acid 10%= nitric acid 20%= nitrous fumes, dry+ ozoneO petroleum ether (hydrocarbon mixture)+ petroleum spirit (for dry cleaning, free of aromatics)= phenol= potassium cyanide+ potassium permanganate, 10% in water+ potassium sulphate, saturated solution in water+ propionic acid 20%+ sodium bicarbonate, saturated solution in water+ sodium chloride, saturated solution in waterO sulphur dioxide= sulphuric acid, conc.+ sulphuric acid 50%= toluene= trichloroethylene

2. Disinfectants= carbolic acid+ hydrogen peroxideO iodine, tincture+ perhydrol

3. Pharmaceuticals, cosmetics+ lanolin= nail varnish remover

4. Foodstuffs, drinks and tobacco= allspice+ coffee+ edible oil+ fruit juices+ glucose+ linseed oil= nutmeg+ sugar solution, saturated+ vegetable juices+ vegetable oil

5. Detergents, rinsing and cleaning agents+ Ajax

O Persil

+ Pril

+ silicone oil emulsion+ soft soapO tuba carpet shampoo conc.

6. Technical oils and greases+ Baysilone fluids (silicone fluids)= brake fluid (ATE)= camphor oilO diesel oil+ fish liver oil+ hydraulic fluid (Vac HLP 16)+ paraffin oil+ silicone oil+ turpentine substituteO varnish

7. Adhesives and sealants+ Cellux adhesive films+ glaziers putty+ insulating tape+ rubber (free of plasticiser)

8. Polishes and anti-static agents+ Delu anti-static solution+ Perspex polish 3

+ Plexiklar

+ Polifac grinding paste

9. InksO multimarker (Faber Castell)+ pelican royal blue 4001

10. Miscellaneous+ battery acid+ chrome oxide green (grinding paste)+ cleaning petrol+ coal gas+ exhaust fumes, acidic= kerosene, (aviation fuel)= motor fuel, high octaneO motor fuel, ordinary grade+ polyethyleneO polymeric plasticisers= tannic acid= thinners= white spirit

+ Resistance O Limited Resistance = Not Resistant

Chemical Resistance Table (Standard Polycarbonate)

Polycarbonate

This information and technical data advice, whether verbal, in writing or through trials, is given in good faith without warranty. This also applies where proprietary rights of third parties are involved. This advice does not release you from the obligation to check its validity.