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RISK ASSESSMENT

STUDY REPORT

For

Aarti Drugs Limited

Plot No 211/213

Rev 0

June 2014

QRA Study Report for ADL

J015 QRA Sarigam Aarti Drugs Rev0

CONTENTS

REPORT APPROVAL FORM I

ABBREVIATIONS II

EXECUTIVE SUMMARY III

1 INTRODUCTION 1-1

1.1 GENERAL 1-1

1.2 BRIEF DESCRIPTION OF FACILITY 1-1

1.3 WEATHER CONDITIONS 1-1

1.4 PLANNING AND EXECUTION OF THE ASSIGNMENT 1-3

2 HAZARD IDENTIFICATION 2-1

2.1 ENUMERATION AND SELECTION OF INCIDENTS 2-1

2.2 CHARACTERISING THE FAILURES 2-2

3 RISK ANALYSIS CALCULATIONS 3-1

3.1 CONSEQUENCE CALCULATIONS 3-1

3.2 DAMAGE CRITERIA 3-1

3.3 CONSEQUENCE ANALYSIS CALCULATIONS 3-6

4 RISK ANALYSIS 4-1

4.1 INDIVIDUAL RISK 4-1

4.2 SOCIETAL RISK 4-5

5 CONCLUSIONS & RECOMMENDATIONS 5-9

6 REFERENCE 6-1

APPENDIX A – ASSUMPTIONS A-1

Contours


J015 QRA Sarigam Aarti Drugs Rev0

LIST OF TABLES

Table 2-1: Major Accident Events 2-1

Table 3-1: Damages to Human Life Due to Heat Radiation 3-3

Table 3-2: Effects Due To Incident Radiation Intensity 3-4

Table 3-3: Damage Due To Overpressures 3-5

Table 4-1: Individual Risk Contribution from various Release Scenarios 4-1

Table 4-2: Societal Risk Contribution for various Release Scenarios 4-5

Table 5-1: Conclusion for IR/SR 5-9

LIST OF FIGURES

Figure 4-1 : F-N Curve for the Facility 4-5


J015 QRA Sarigam Aarti Drugs Rev0 i

SAWALI

CONSULTANCY REPORT APPROVAL FORM Job No.: J015

Client: AARTI DRUGS LIMITED

Report Title: Risk Assessment Study

Rev No. 0 SIGNATURE DATE

Prepared by: Kavita Patwardhan 11/06/2014

Checked by: Sunanda Rahurkar 12/06/2014

Approved by: Sunanda Rahurkar 12/06/2014

Revisions

Rev Revision By Checked Approved Date

Client Approval Of Report:

Rev

No. Signature Date

0

This document is confidential and has been produced for the purpose of the above mentioned study and is

only suitable for use in connection therewith.

Any liability arising out of use of this document by the above mentioned client or third party, for purposes not

wholly connected with the above mentioned study, shall be the responsibility of the above mentioned client

who shall indemnify Sawali Consultancy against all claims, damages and losses arising out of such use.


J015 QRA Sarigam Aarti Drugs Rev0 ii

ABBREVIATIONS

ALARP As Low As Reasonably Practicable

ADL Aarti Drugs Limited

IR Individual Risk

LEL Lower Explosive Limit

LFL Lower Flammability Limit

LP Low Pressure

MAE Major Accident Event

NR Not Reached

PLL Potential Loss of Life

RA Risk Assessment

SR Societal Risk


J015 QRA Sarigam Aarti Drugs Rev0 iii

EXECUTIVE SUMMARY

Aarti Drugs Limited, Metformin Hydrochloride manufacturing plant is located at Sarigam,

GIDC in Gujarat.

Aarti Drugs Limited has engaged Sawali Consultancy, for carrying out Risk Assessment

(RA) for the operating facility at Sarigam. The present report is the RA Study report for

the facilities based on the design & operating information and suitable conservative

assumptions. Based on the RA study, the following conclusions and recommendations

emerge:

CONCLUSIONS

Based on the QRA results, the Individual Risk as well as Societal Risk falls in below

ALARP (As Low As Reasonably Practicable) region

The summary of consequence analysis has been presented in the summary table

Based on this study, the following conclusions have been reached:

Conclusion for IR/SR

1

Individual Risk (IR)

The IR value for the Aarti Drugs Limited is estimated at 2.47E-06 per year, which is

in ALARP region.

2

Expected Number of Fatalities (PLL)

The estimated overall Potential Loss of Life (PLL) for the plant population is

estimated at 0.82 E-06 per year.

3

Societal Risk (F-N Curve)

The F-N curves show that societal risk for the overall population considered falls

below the ALARP region (10-3 to 10-5) i.e. in the acceptable region.

In the majority of failure scenarios considered, damage to adjacent equipment or tank is

likely in event of fire/ explosion. Radiation received by surrounding equipment or tanks

could be sufficient to cause overheating/ explosion of the equipment or tank.


J015 QRA Sarigam Aarti Drugs Rev0 iv

RECOMMENDATIONS

Use of mechanical equipment and tools that can generate sparks in operation should

be avoided within the process areas.

Ensure strict implementation of ‘NO SMOKING’ and ‘NO MOBILE’ at the facility to

minimize ignition chances. The vehicles entering inside the plant should be ensured

to be fitted with flame arrestors.

During unloading of various solvents, proper grounding of the road tankers to be

ensured.

Emergency procedures should be well rehearsed and state of readiness to be

achieved.

As in case of a fire at the terminal, escape and evacuation routes are expected get

impaired due to high radiation levels (>6.3kW/m2), therefore, EERA shall be done for

the terminal.

Small leaks could occur frequently in routine operations like pump seal failure,

sample point valve or drain valve left open, flange leak etc. They should be attended

to immediately as they could escalate.

In case of any leakage, evacuate staffs at the leakage affected area and guide them

to a safe place; prevent entry of unnecessary personnel into the affected area; and

isolate ignition source. Personnel for emergency treatment should stop leakage in a

safe manner.


J015 QRA Sarigam Aarti Drugs Rev0 1-1

1 INTRODUCTION

1.1 GENERAL

Aarti Drugs Limited has engaged Sawali Consultancy, for carrying out Risk Assessment

(RA) for the operating facility at Sarigam. The present report is the RA Study report for

the facilities based on the design & operating information and suitable conservative

assumptions. Based on the RA study, the following conclusions and recommendations

emerge:

1.2 BRIEF DESCRIPTION OF FACILITY

Aarti Drugs Limited, Metformin Hydrochloride manufacturing plant is located at plot no.

211 & 213, Sarigam, GIDC in Gujarat

The present factory premises have occupied 4213.31 M2 out of 8662 M2. Non-polluting

and are not in the manufacture of pesticides, antibiotics or steroids. The GIDC supplies

filtered potable water, which is basically river water. The electricity is supplied by the

Gujarat Electricity Board and supply line is 750 KV.

1.3 WEATHER CONDITIONS

The consequences arising out of the release of chemicals are dependent among other

things on the prevailing meteorological conditions. This section describes the influence

of these conditions.

1.3.1 Stability Class

Dispersion of gases or vapours largely depends upon the Stability Class. Various

stability classes that are defined as Pasquill classes are:

- A Very Unstable

- B Unstable

- C Slightly Unstable

- D Neutral

- E Stable

- F Very Stable

The stability class for a particular location is generally dependent upon:

- Time of the Day (Day or Night)

- Cloud Cover



- Season

- Wind Speed

Six stability classes from A to F are defined while wind speed can take any one of

numerous values. It may thus appear that a large number of outcome cases can be

formulated by considering each one of very many resulting stability class-wind speed

combinations. However, in fact the number of stability class - wind speed combinations

that needs to be considered for formulating outcome cases in any analysis is very

limited. This is because, in nature, only certain combinations of stability class and wind

speed occur. Thus, for instance combinations such as A-3 m/s or B-5 m/s or F-4 m/s do

not occur in nature. As a result only one or two stability class - wind speed combinations

need to be considered to ensure reasonable completeness of Quantitative Risk

assessment study. Furthermore, though wind speeds less than 1 m/s may occur in

practice, none of the available dispe8rsion models, including state-of-art ones, can

handle wind speeds below 1 m/s. Fortunately, wind speed does not influence

consequences as much as stability class and for a given stability class, the influence of

wind speed is relatively less. On the other hand, consequences vary considerably with

stability class for the same speed.

Except during the monsoon months little or no cloud cover along with the prevailing low

wind velocities results in unstable conditions during the day (C or D) and highly stable

conditions (E or F) at night. During the three months of monsoons, the wind velocities

are generally higher and cloud cover generally present. This results in stability class of D

during the day and E or F during the night. The stability class distribution over the year

roughly works out as below:

A - B - C 17%

D 50%

E or F 33%

The following wind velocity/ stability class combinations & frequencies are used for Risk

Assessment.

D – 3 m/s

F – 1.5 m/s

Annual mean air temperature is taken as 33oC, while annual mean humidity is taken as

65% based on weather conditions.



1.4 PLANNING AND EXECUTION OF THE ASSIGNMENT

The initial efforts for the study involved site visit and collection of site information. This

also included discussions on Process and Hazards with Aarti Drugs Limited personnel.

The information required provided familiarity with the project to the team carrying out the

Risk Assessment study. The next part of the study comprised of the Risk Analysis

calculations based on the collected data. These essentially involved release rate and

source strength calculations, dispersion modelling and consequence modelling for the

selected scenarios followed by release probability calculations. Based on RA

calculations, conclusions and recommendations have been stated in section 4 of this

report.



2 HAZARD IDENTIFICATION

2.1 ENUMERATION AND SELECTION OF INCIDENTS

Effective management of a Risk Assessment study requires enumeration and selection

of incidents or scenarios. Enumeration attempts to ensure that no significant incidents

are overlooked; selection tries to reduce the incident outcome cases studied to a

manageable number.

These incidents can be classified under, either of the two categories:

Loss of containment of material, or

Loss of containment of energy.

Unfortunately, there are infinite ways (incidents) by which loss of containment can occur

in either category. For example, leaks of process materials can be of any size, from a

pinhole up to a severed pipeline or ruptured vessel. An explosion can occur in either a

small container or a large container and, in each case, can range from a small "puff" to a

catastrophic detonation.

A technique commonly used to generate an incident list is to consider potential leaks

and major releases from fractures of all process pipelines and vessels. This compilation

should include all pipe work and vessels in direct communication, as these may share a

significant inventory that cannot be isolated in an emergency. The data generated is as

shown below:

Vessel number, description, and dimensions

Materials present

Vessel conditions (phase, temperature, pressure)

Inventory and connecting piping and piping dimensions

The goal of selection is to limit the total number of incident outcome cases, to be studied

to a manageable size, without introducing bias or losing resolution through overlooking

significant incidents or incident outcomes. The purpose of incident selection is to

construct an appropriate set of incidents for the study from the Initial list that has been

generated by the enumeration process. An appropriate set of incidents is the minimum

number of incidents needed to satisfy the requirements of the study and adequately

represent the spectrum of incidents enumerated.



2.2 CHARACTERISING THE FAILURES

Accidental release of flammable or toxic materials can result in severe consequences.

Delayed ignition of flammable vapours can result in blast overpressures covering large

areas. This may lead to extensive loss of life and property. Toxic clouds may cover yet

larger distances due to the lower threshold values in relation to those in case of

explosive clouds (the lower explosive limits). In contrast, fires have localized

consequences. In most of the cases, fires can be put out or contained, but there are very

few mitigating actions that one can take once a vapour cloud has released.

In facilities, like the ones in question, the main hazard arises due to the possibility of

leakage of flammable and toxic materials. To formulate a structured approach to

identification of hazards, an understanding of contributory factors is essential.

2.2.1 Operating Parameters

Operating parameters (Temperature, Pressure & Phase) may vary subject to the

processing, storage, handling, loading/ unloading and transportation conditions.

Potential vapour release of the materials handled depends significantly on these

conditions. Temperature and pressure conditions provided by ADL have been used for

Consequence Analysis.

2.2.2 Inventory

Inventory Analysis is commonly used in understanding the relative hazards and short

listing of release scenarios. Inventory plays an important role with regard to the potential

hazard. A practice commonly used to generate an incident list is to consider potential

leaks and major releases from fractures of pipelines and vessels containing sizable

inventories. The potential vapour release (source strength) depends upon the quantity of

liquid release, the properties of the materials and the operating conditions (pressure,

temperature).

2.2.3 Loss of Containment

Inventory can be discharged into the environment due to Loss of Containment. Various

causes and modes for such an eventuality have been described. Certain features of

materials to be handled at the facility need to be clearly understood to firstly list out all

significant release cases and then to short list release scenarios for a detailed

examination.



Inventory release can be either instantaneous or continuous. Failure of a vessel leading

to an instantaneous outflow assumes the sudden appearance of such a major crack that

practically all of the contents above the crack shall be released in a very short time. The

more likely event is the case of inventory release from a hole in a pipe connected to the

vessel. The flow rate will depend on the size of the hole as well as on the pressure in

front of the hole, prior to the accident. Such pressure is dependent on the pressure in the

system.

For a liquid release, the vapourization of released liquid depends on the vapour pressure

and weather conditions. Such consideration and others have been kept in mind while

performing calculations.



2.2.4 EVENT TREE ANALYSIS

Following is a generalized event tree which has been used in the current QRA study



2.2.5 Hazardous Scenarios

Based on the methodology discussed above a set of appropriate scenarios (MAEs) were

generated to carry out Quantitative Risk assessment calculations, as listed below:

Table 2-1: Major Accident Events

S.No Major Accident Events

1. Leak of Xylene tank

2. Rupture of xylene tank

3. Leak of Methanol tank

4. Rupture of Methanol tank

5. Leak of Toluene tank

6. Rupture of Toluene tank

7. Leak of Xylene tanker

8. Rupture of xylene tanker

9. Leak of Methanol tanker

10. Rupture of Methanol tanker

11. Leak of Toluene tanker

12. Rupture of Toluene tanker



3 RISK ANALYSIS CALCULATIONS

3.1 CONSEQUENCE CALCULATIONS

HAZARDS ASSOCIATED WITH FLAMMABLE MATERIALS

ADL handles a number of hazardous materials like Xylene, methanol and Toluene. The

major hazards from these types of materials may be fire radiation and explosion. Fire

and explosion hazards depend on the range of flammable concentrations of the material

in air among all common gaseous fuels. Any spillage or loss of containment of heavier

hydrocarbons may create a highly flammable pool of liquid around the source of release.

High entrainment of gas phase in the liquid phase can lead to jet fires. If released at

temperatures higher than the normal boiling point they can flash significantly.

3.2 DAMAGE CRITERIA

In consequence, analysis, use is made of a number of calculation models to estimate the

physical effects of an accident (spill of hazardous material) and to predict the damage

(lethality, injury, material destruction) of the effects. The calculations can roughly be

divided in three major groups:

a) Determination of the source strength parameters;

b) Determination of the consequential effects;

c) Determination of the damage or damage distances

The basic physical effect models consist of the following:

3.2.1 Source Strength Parameters

Calculation of the outflow of liquid out of equipment or tank or pipe, in case of

rupture.

Calculation, in case of liquid outflow, of the instantaneous flash evapouration and of

the dimensions of the remaining liquid pool.

Calculation of the evapouration rate, as a function of volatility of the material, pool

dimensions and wind velocity.

Source strength equals pump capacities, etc. in some cases of pump discharge line

ruptures for catastrophic cases.



3.2.2 Consequential effects

Dispersion of gaseous material in the atmosphere as a function of source strength,

relative density of the gas, weather conditions and topographical situation of the

surrounding area.

Intensity of heat radiation [in kW/m2] due to a fire, as a function of the distance to the

source.

Energy of vapour cloud explosions [in N/m2], as a function of the distance to the

distance of the exploding cloud.

Concentration of gaseous material in the atmosphere, due to the dispersion of

evapourated chemical. The latter can be either explosive.

It may be obvious, that the types of models that must be used in a specific risk study

strongly depend upon the type of material involved:

Gas, vapour, liquid, solid?

Inflammable, explosive,

Stored at high/ low temperatures or pressure?

Controlled outflow (pump Inventory) or catastrophic failure?

3.2.3 Selection of Damage Criteria

The damage criterion gives the relation between extent of the physical effects

(exposure) and the percentage of the people that will be killed or injured due to those

effects. The knowledge about these relations depends strongly on the nature of the

exposure. For instance, a lot is known about the damage caused by heat radiation, than

about the damage due to toxic exposure, and for these toxic effects, the knowledge

differs strongly between different materials. In Consequence Analysis studies, in

principle three types of exposure to hazardous effects are distinguished:

1. Heat radiation, from a jet, pool fire or flash fire.

2. Explosion

3. Heat Radiation

The consequences caused by exposure to heat radiation are function of:

The radiation energy onto the human body [kW/m2];

The exposure duration [sec];

The protection of the skin tissue (clothed or naked body).



The limits for 1% of the exposed people to be killed due to heat radiation, and for

second-degree burns are given in the table below:

Table 3-1: Damages to Human Life Due to Heat Radiation

Exposure

Duration

Radiation energy

(1% lethality,

kW/m2

Radiation energy

for 2nd degree

burns, kW/m2

Radiation energy

for first degree

burns, kW/m2

10 Sec 21.2 16 12.5

30 Sec 9.3 7.0 4.0

Since in practical situations, only the people outside will be exposed to heat radiation. In

case of a fire, it is reasonable to assume the protection by clothing. It can be assumed

that people would be able to find a cover or a shield against thermal radiation in 10-sec.

time. Furthermore, 100% lethality may be assumed for all people suffering from direct

contact with flames, such as the pool fire, a flash fire or a jet flame. The effects due to

relatively lesser incident radiation intensity are given below:



Table 3-2: Effects Due To Incident Radiation Intensity

Radiation Intensity

(kW/m2)

Casualty Threshold

0.7 Equivalent to Solar Radiation

1.6 No discomfort for long exposure

4.0 Sufficient to cause pain within 20 sec. Blistering of skin

(first degree burns are likely)

9.33 Pain threshold reached after 8 sec. Second degree burns

after 20 sec. 1% lethality.

12.7 Minimum energy required for piloted ignition of wood,

melting plastic tubing etc. 10% lethality

18.47 50% lethality

36.56 99% lethality

The actual results would be less severe due to the various assumptions made in the

models arising out of the flame geometry, emissivity, angle of incidence, view factor and

others. Upon ignition, a spilled liquid would burn in the form of a large turbulent diffusion

flame. The size of the flame would depend upon the spill surface and the thermo-

chemical properties of the spilled liquid. In particular, the diameter of the fire (if not

confined to a dyke), the visible height of the flame, the tilt and drag of the flame due to

wind can be correlated to the burning velocity of the liquid. The radiative output of the

flame would be dependent upon the fire size, extent of mixing with air and the flame

temperature. Some fraction of the radiation is absorbed by carbon dioxide and water

vapour in the intervening atmosphere. In addition, large pool fires produce thick smoke,

which can significantly obscure flame radiation. Finally the incident flux at an observer

location would depend upon the radiation view factor, which is a function of the distance

from the flame surface, the observer’s orientation and the flame geometry.

Estimation of the thermal radiation hazards from pool/ jet fires essentially involves 3

steps; characterization of flame geometry, approximation of the radiative properties of



the fire and calculation of safe separation distances to specified levels of thermal

radiation.

Explosion

In case of vapour cloud explosion, two physical effects may occur:

flash fire over the whole length of the explosive gas cloud;

A blast wave, with typical peak overpressures circular around ignition source.

As explained above, 100% lethality is assumed for all people who are present within the

cloud proper.

For the blast wave, the lethality criterion is based on:

Peak overpressure of 0.1 bars will cause serious damage to 10% of the

housing/structures.

Falling fragments will kill one of each eight persons in the destroyed buildings.

The following damage criteria may be distinguished with respect to the peak

overpressures resulting from a blast wave:

Table 3-3: Damage Due To Overpressures

Peak Overpressure, bar Damage Type

0.83 Total destruction

0.30 Heavy damage, nearly complete destruction of houses

0.27 Cladding of light industrial building ruptures

0.2 Steel frame buildings distorted and pulled from

foundations

0.16 Lower limit of serious structural damage

0.14 Partial collapse of walls and roofs of houses

0.027 Limited minor structural damage

0.01 Typical pressure of glass breakage

From this it may be concluded that p = 0.17 E+5 pa corresponds approximately with 1%

lethality. Furthermore it is assumed that everyone inside an area in which the peak

overpressure is greater than 0.17 E+5 pa will be wounded by mechanical damage. For

the gas cloud explosion this will be inside a circle with the ignition source as its centre.



3.3 CONSEQUENCE ANALYSIS CALCULATIONS

This section documents the consequence-distance calculations. A Maximum Credible

Accident (MCA) can be characterized as the worst credible accident. Another aspect, in

which the pessimistic approach of MCA studies appears, is the atmospheric condition

that is used for dispersion calculations. In general, a very stable atmosphere (Pasquill

class F) and a low wind speed (1.5 m/s) are assumed. These conditions result in the

lowest dispersion velocity & consequently in the highest vapour concentrations and the

largest damage distances. Less pessimistic assumptions (e.g. neutral weather, wind

speed 3 m/s), which are generally the more average conditions, result in smaller

damage distances.

In Risk Assessment studies contributions from low frequency - high outcome effect as

well as high frequency - low outcome events are distinguished. The objective of the

study is making the facility safer and have better emergency planning, hence only

holistic & conservative assumptions are used for obvious reasons. Hence though the

outcomes may look pessimistic, the planning for emergency concept should be borne in

mind whilst interpreting the results. The Consequence Analysis has been done for

selected scenarios for weather conditions D-3 m/sec and F-1.5 m/sec.



CONSEQUENCE ANALYSIS CALCULATIONS



Sc # 1 Small leak from Xylene tank - Pool fire

Parameters

Temperature - Atmospheric

Pressure - Atmospheric

Capacity - 25 kL

Heat Radiation Model

Exposure duration - 30 sec

Effective Radius of the pool - 4.3 m

(100 % fatality within the pool area)

For exposure duration of 30 sec. and protected human body the damage distances are

as follows:

Pool Fire Model

Percent Lethality Thermal Load

(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)

First Degree Burns 4.0 31.9 33.8

1 9.33 22.2 25.2

10 12.70 18.8 21.9

50 18.47 14.5 16.4

99 36.56 9.4 9.8

Probability

Base Frequency - 5E-06 per year

Ignition Probability - 0.3

Accident Probability - 5E-06 * 0.3 per year/ tank

= 1.5E-06 per year/tank





Sc # 2 Small leak from Xylene tank - Flash Fire/ VCE

Parameters



Capacity - 25 kL

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

70000 4.0 4.3

11000 6.2 6.9

Vapour Cloud Explosion Model

Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 19.2 10 20.1 10

0.1379 12.4 10 12.6 10

0.2068 11.8 10 12.0 10

Probability

Base Frequency - 5E-06 per year/ tank








Sc # 3 Rupture of Xylene tank - Pool fire

Parameters



Capacity - 25 kL






as follows:

Pool fire Model


(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)


1 9.33 22.1 25.2

10 12.70 18.7 21.8

50 18.47 14.4 16.4

99 36.46 9.4 9.7

Probability









Sc # 4 Rupture of Xylen tank - Flash Fire/ VCE

Parameters



Capacity - 25 kL

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

70000 4.0 4.3

11000 6.2 6.9


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 19.2 10 20.0 10

0.1379 12.4 10 12.6 10

0.2068 11.8 10 12.0 10

Probability









Sc # 5 Small leak from Methanol tank -Pool fire

Parameters



Capacity - 25 KL






as follows:

Pool Fire Model

Percent Lethality

Thermal Load

(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)


1 9.33 105.7 105.4

10 12.70 68.8 72.2

50 18.47 57.1 61.1

99 36.46 45.6 44.9

Probability









Sc # 6 Small leak from Methanol tank - Flash Fire/ VCE

Parameters



Capacity - 25KL

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

360000 75.7 43.3

73000 38.9 24.2


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 207.4 70 95.5 40

0.1379 105.6 70 54.4 40

0.2068 97.5 70 51.1 40

Probability









Sc # 7 Rupture of Methanol tank - Pool fire

Parameters



Capacity - 25KL






as follows:

Pool Fire Model

Percent Lethality

Thermal Load

(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)


1 9.33 104.9 106.2

10 12.70 66.7 71.2

50 18.47 54.6 59.6

99 36.46 76.1 79.9

Probability









Sc # 8 Rupture of Methanol tank - Flash Fire/ VCE

Parameters



Capacity - 25KL

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

360000 121.6 130.4

73000 749.6 483.7


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 168.0 90 151.6 30

0.1379 108.3 90 57.4 30

0.2068 104.2 90 53.1 30

Probability









Sc # 9 Small leak from Toluene tank - Pool fire

Parameters



Capacity - 25 KL






as follows:

Pool fire Model


(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)


1 9.33 15.7 17.2

10 12.70 13.6 15.4

50 18.47 11.1 12.8

99 36.46 6.7 7.3

Probability




= 1.5E-06 per year/ tank





Sc # 10 Leak from toluene tank - Flash Fire/ VCE

Parameters



Capacity - 25 KL

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

71000 0.76 0.77

12000 0.05 0.3


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 44.4 20 25.3 10

0.1379 26.3 20 13.9 10

0.2068 24.9 20 13.0 10

Probability




= 1.5E-06 per year/ tank





Sc # 11 Rupture of toluene tank -Pool fire

Parameters



Capacity - 25 KL





as follows:

Pool fire Model


(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)


1 9.33 13.3 14.9

10 12.70 11.2 13.1

50 18.47 8.6 10.4

99 36.46 4.3 4.9

Probability









Sc # 12 Rupture of Toluene tank - Flash Fire/ VCE

Parameters



Capacity - 25 KL

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

71000 3.5 3.55

12000 15.1 15.6


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 107.9 10 104.1 10

0.1379 39.8 10 35.8 10

0.2068 35.3 10 32.2 10

Probability









Sc # 13 Small leak from Xylene tanker - Pool fire

Parameters



Capacity - 20 MT






as follows:

Pool fire Model


(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)


1 9.33 34.8 37.7

10 12.70 30.1 30.3

50 18.47 30.1 30.3

99 36.46 Not Reached Not Reached

Probability

Base Frequency - 5E-07 per year/ tanker


Accident Probability - 5E-07 * 0.3 per year/ tanker

= 1.5E-07 per year/ tanker





Sc # 14 Small leak from Xylene tanker - Flash Fire/ VCE

Parameters



Capacity - 20 MT

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

70000 4.4 4.0

11000 21.5 18.1


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 82.7 30 81.6 30

0.1379 43.7 30 43.4 30

0.2068 40.6 30 40.4 30

Probability




= 1.5E-07 per year/tanker





Sc # 15 Rupture of Xylene tanker - Pool fire

Parameters



Capacity - 20 MT






as follows:

Pool fire Model


(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)


1 9.33 34.8 37.7

10 12.70 30.1 30.3

50 18.47 30.1 30.3


Probability




= 3E-06 per year/tanker





Sc # 16 Rupture of Xylene tanker - Flash Fire/ VCE

Parameters



Capacity - 20 MT

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

70000 4.4 4.0

11000 21.5 18.0


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 82.7 30 81.6 30

0.1379 43.7 30 43.4 30

0.2068 40.6 30 40.3 30

Probability









Sc # 17 Small leak from Methanol tanker - Flash Fire/ VCE

Parameters



Capacity - 10 MT

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

360000 4.8 4.9

73000 31.5 23.9


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 146.7 60 87.5 40

0.1379 82.4 60 52.3 40

0.2068 77.4 60 49.5 40

Probability









Sc # 18 Rupture of Methanol tanker - Pool fire

Parameters



Capacity - 10 MT






as follows:

Pool fire Model


(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)


1 9.33 50.7 53.3

10 12.70 44.5 47.6

50 18.47 36.2 38.9

99 36.46 29.9 29.7

Probability




= 3E-06 per year/ tanker





Sc # 19 Rupture of Methanol tanker - Flash Fire/VCE

Parameters



Capacity - 10 kL

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

360000 4.8 4.8

73000 31.4 23.9


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 146.7 60 87.5 40

0.1379 82.5 60 52.3 40

0.2068 77.4 60 49.5 40

Probability









Sc # 20 Small leak from Toluene tanker - Pool fire

Parameters



Capacity - 10 MT






as follows:

Pool fire Model


(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)


1 9.33 34.4 37.3

10 12.70 29.7 29.8

50 18.47 29.6 29.7


Probability









Sc # 21 Leak from Toluene tanker - Flash Fire/ VCE

Parameters



Capacity - 10 MT

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

71000 5.9 6.2

12000 46.5 31.4


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 191.7 50 105.9 40

0.1379 86.7 50 57.1 40

0.2068 78.4 50 53.2 40

Probability









Sc # 22 Rupture of Toluene tanker - Pool fire

Parameters



Capacity - 10 MT






as follows:

Pool fire Model


(kW/m2)

Effect Distance (m)

F (1.5 m/s) D (3 m/s)


1 9.33 34.4 37.3

10 12.70 29.6 29.8

50 18.47 29.7 29.7


Probability









Sc # 23 Rupture of Toluene tanker - Flash Fire/ VCE

Parameters



Capacity - 10 MT

Flash Fire Model

Concentration (ppm)

Distance (m)

F (1.5 m/s) D (3 m/s)

71000 5.9 6.2

12000 46.5 31.3


Damage

Type

F (1.5 m/s) D (3 m/s)

Effect

Distance(m)

Ignition Centre

(m)

Effect Distance

(m)

Ignition Centre

(m)

0.02068 191.7 50 105.9 40

0.1379 86.7 50 57.1 40

0.2068 78.4 50 53.2 40

Probability









4 RISK ANALYSIS

4.1 INDIVIDUAL RISK

The IR value for the Aarti drugs limited comes out to be 2.47 E-06 per year which falls

under acceptable region of risk acceptance criteria. The IR acceptance criteria are those

adapted by UK HSE and presented below as risk triangle.

Given below are the Individual risk levels and contributions of various release scenarios

as calculated from the risk analysis.

Table 4-1: Individual Risk Contribution from various Release Scenarios

Scenario

Individual Risk

% Contribution

Leakage of Xylene tank - Pool fire 4.255%

Leakage of Xylene tank - Flash Fire/ VCE 4.255%

Rupture of Xylene tank - Pool fire 4.255%



Scenario

Individual Risk

% Contribution

Rupture of Xylene tank - Flash Fire/ VCE 4.255%

Leakage of Methanol tank -Pool fire 4.355%

Leakage of Methanol tank - Flash Fire/ VCE 4.255%

Rupture of Methanol tank - Pool fire 4.255%

Rupture of Methanol tank - Flash Fire/ VCE 4.255%

Leakage of toluene tank - Pool fire 4.255%

Leakage of toluene tank - Flash Fire/ VCE 4.255%

Rupture of toluene tank -Pool fire 4.255%

Rupture of toluene tank - Flash Fire/ VCE 4.255%

Leakage of Xylene tanker - Pool fire 4.255%

Leakage of Xylene tanker - Flash Fire/ VCE 4.255%

Rupture of Xylene tanker - Pool fire 4.255%

Rupture of Xylene tanker - Flash Fire/ VCE 0.426%

Leakage of Methanol tanker - Pool fire 0.426%

Leakage of methanol tanker - Flash Fire/ VCE 8.511%

Rupture of Methanol tanker - Pool fire 8.511%

Rupture of methanol tanker – Flash Fire/VCE 0.426%

Leakage of Toluene tanker - Pool fire 0.426%



Scenario

Individual Risk

% Contribution

Leakage of toluene tanker - Flash Fire/ VCE 8.511%

Rupture of Toluene tanker - Pool fire 8.511%

Rupture of Toluene tanker - Flash Fire/ VCE 0.426%

Total 100 %

The individual Risk contributors in the form of pie chart are given below





4.2 SOCIETAL RISK

Societal risk is the risk experienced by the group of personnel exposed in a given time

period. Societal risk is generally used to describe multiple injury accidents/fatalities, or to

describe risks to “unnamed” individuals, which include the public and is usually

described by F-N Curves. Based on Risk Analysis calculations for ADL facility, the

societal/ group risk is found to be 2.69 E-07 per year. Societal risk results have been

presented in the following FN curve

Figure 4-1 : F-N Curve for the Facility

Given below are the societal risk levels and contributions of various release scenarios as

calculated from the Risk Analysis

Table 4-2: Societal Risk Contribution for various Release Scenarios

Scenario

Societal Risk

% Contribution

Leakage of Xylene tank - Pool fire 0.42%

Leakage of Xylene tank - Flash Fire/ VCE 0.22%



Scenario

Societal Risk

% Contribution

Rupture of Xylene tank - Pool fire 0.42%

Rupture of Xylene tank - Flash Fire/ VCE 0.22%

Leakage of Methanol tank -Pool fire 5.94%

Leakage of Methanol tank - Flash Fire/ VCE 14.60%

Rupture of Methanol tank - Pool fire 5.67%

Rupture of Methanol tank - Flash Fire/ VCE 16.64%

Leakage of toluene tank - Pool fire 0.25%

Leakage of toluene tank - Flash Fire/ VCE 0.95%

Rupture of toluene tank -Pool fire 0.17%

Rupture of toluene tank - Flash Fire/ VCE 1.92%

Leakage of Xylene tanker - Pool fire 1.42%

Leakage of Xylene tanker - Flash Fire/ VCE 2.53%

Rupture of Xylene tanker - Pool fire 1.42%

Rupture of Xylene tanker - Flash Fire/ VCE 0.25%

Leakage of Methanol tanker - Pool fire 0.24%

Leakage of methanol tanker - Flash Fire/ VCE 18.38%

Rupture of Methanol tanker - Pool fire 4.71%

Rupture of methanol tanker – Flash Fire/VCE 0.92%



Scenario

Societal Risk

% Contribution

Leakage of Toluene tanker - Pool fire 0.14%

Leakage of toluene tanker - Flash Fire/ VCE 18.89%

Rupture of Toluene tanker - Pool fire 2.73%

Rupture of Toluene tanker - Flash Fire/ VCE 0.94%

Total 100 %

Based on the above, the major risk contributors to societal risk are:

1. Leakage of toluene tanker - Flash Fire/ VCE

2. Leakage of Methanol tank - Flash Fire/ VCE

3. Leakage of methanol tanker - Flash Fire/ VCE

4. Rupture of Methanol tank - Flash Fire/ VCE

The Group Risk contributors in the form of pie chart are given below:





5 CONCLUSIONS & RECOMMENDATIONS

Based on the QRA results, the Individual Risk as well as Societal Risk falls in below

ALARP (As Low As Reasonably Practicable) region

The summary of consequence analysis has been presented in the summary table

Based on this study, the following conclusions have been reached:

Table 5-1: Conclusion for IR/SR

1

Individual Risk (IR)

The IR value for the Aarti Drugs Limited is estimated at 2.47E-06 per year, which is

in ALARP region.

2

Expected Number of Fatalities (PLL)

The estimated overall Potential Loss of Life (PLL) for the plant population is

estimated at 0.82 E-06 per year.

3

Societal Risk (F-N Curve)

The F-N curves show that societal risk for the overall population considered falls

below the ALARP region (10-3 to 10-5) i.e. in the acceptable region.

In the majority of failure scenarios considered, damage to adjacent equipment or tank is

likely in event of fire/ explosion. Radiation received by surrounding equipment or tanks

could be sufficient to cause overheating/ explosion of the equipment or tank.

RECOMMENDATIONS

Use of mechanical equipment and tools that can generate sparks in operation should

be avoided within the process areas.

Ensure strict implementation of ‘NO SMOKING’ and ‘NO MOBILE’ at the facility to

minimize ignition chances. The vehicles entering inside the plant should be ensured

to be fitted with flame arrestors.

During unloading of various solvents, proper grounding of the road tankers to be

ensured.

Emergency procedures should be well rehearsed and state of readiness to be

achieved.

As in case of a fire at the terminal, escape and evacuation routes are expected get

impaired due to high radiation levels (>6.3kW/m2), therefore, EERA shall be done for



the terminal.

Small leaks could occur frequently in routine operations like pump seal failure,

sample point valve or drain valve left open, flange leak etc. They should be attended

to immediately as they could escalate.

In case of any leakage, evacuate staffs at the leakage affected area and guide them

to a safe place; prevent entry of unnecessary personnel into the affected area; and

isolate ignition source. Personnel for emergency treatment should stop leakage in a

safe manner.



6 REFERENCE

1. TNO Purple Book (CPR 18E) – Guideline For Quantitative Risk Assessment

2. TNO Green Book (CPR16E) - Methods For The Determination Of Possible

Damage

3. International Association of Oil & Gas Producers (OGP)- Risk Assessment Data

Directory – Ignition Probabilities.

4. Phast & Risk Manual provided By DNV.


J015 QRA Sarigam Aarti Drugs Rev0 A-1

APPENDIX A – ASSUMPTIONS



1 PROCESS HAZARDS ASSUMPTIONS Rev: 0 Date: 10/06/2014

1.1 Process Release Hole Sizes

Description of Assumption:

Following leak sizes have been considered for MAEs mentioned in the report:

Table 1.1 Specified Release Hole Sizes

Category Specified Release Hole Size (mm)

Large Leak 80% of maximum line size

Note: Catastrophic Rupture is considered additionally

Comments:



2 WEATHER DATA ASSUMPTIONS Rev: 0 Date: 10/062014


The following weather conditions has been assumed for consequence calculations:

D-3 m/sec

F-1.5 m/sec

The average ambient temperature is taken as 33oC and relative humidity as 65%.

Comments: The weather data is referred from Climatological Tables, India Meteorological Department.



3 SAFETY SYSTEMS AND EMERGENCY. RESPONSE ASSUMPTIONS

Rev: 0 Date: 10/06/2014

3.1 Effect of Thermal Radiation


Effect of Thermal radiation levels are listed in the table below.

Table 3.1 Effects due to Incident Radiation Intensity

INCIDENT RADIATION – kW/m2 TYPE OF DAMAGE

0.7 Equivalent to Solar Radiation

1.6 No discomfort for long exposure

4.0 Sufficient to cause pain within 20 sec. Blistering

of skin (first degree burns are likely)

9.3 Pain threshold reached after 8 sec. Second

degree burns after 20 sec. 1% lethality.

12.5 Minimum energy required for piloted ignition of

wood, melting plastic tubing etc. 10% lethality.

18.47 50% lethality.

36.56 99% lethality.

Comments: The effects of thermal radiation has been obtained from TNO Green Book



3 SAFETY SYSTEMS AND EMERGENCY. RESPONSE ASSUMPTIONS

Rev: 0 Date: 10/06/2014

3.2 Explosion Overpressure Effect Criteria


The explosion overpressure effect criteria are listed in following table:

Table 3.2 Damage due to Explosion Overpressure

Peak Overpressure, bar Damage Type

0.83 Total destruction

0.30 Heavy damage, nearly complete destruction of houses

0.27 Cladding of light industrial building ruptures

0.2 Steel frame buildings distorted and pulled from

foundations

0.16 Lower limit of serious structural damage

0.14 Partial collapse of walls and roofs of houses

0.027 Limited minor structural damage

0.01 Typical pressure of glass breakage

Comments: The effects of overpressure has been obtained from TNO Green Book



3 RISK CALCULATION ASSUMPTIONS Rev: 0 Date: 10/06/2014

3.1 Vulnerabilities used for the Polysilicon Facility


Table 3.2 Vulnerability values

Hazard Impact Level Outdoor Indoor

Pool Fire Radiation 0.7 0.2

Flash Fire LFL 1 0.1

Overpressure

Light Explosion (up to 100 mbar) 0 0.16

Heavy Explosion (> 100 mbar) 0.1 1

.

Comments:



3 RISK CALCULATION ASSUMPTIONS Rev: 0 Date: 10/06/2014

3.2 Risk Analysis Criteria


Following Criteria have been used for the risk analysis:

Comments:

CONTOURS

Legends:

Fire due to release of toluene

Explosion due to release of toluene

Fire due to release of xylene

Explosion due to release of xylene

Fire due to release of methanol

Explosion due to release of methanol

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