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Report on

Quantitative Risk Assessment

Of

Marketing Terminal, Mathura Refinery

Indian Oil Corporation Limited

By

Cholamandalam MS Risk Services Ltd. (An ISO 9001:2008 Certified Company)

Chennai, India.

www.cholarisk.com

August, 2011

http://www.cholarisk.com/

QRA Study Report for Marketing Terminal, Mathura Refinery, IOCL

Document Id QRA/IOCL MT /

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DOCUMENT HISTORY

S. No.

Document Identification

Revision Comments / Nature of

Changes No Date

1 QRA/IOCL MT / 11-12/

01 00 25

th August, 2011

Preparation of Original Document

2 QRA/IOCL MT / 11-12/

01 01 3

rd September, 2011 Incorporation of comments

Prepared By Reviewed By Verified By Approved By

G Venkata Kiran

Asst. Manager

R. Subramanian

Asst. General Manager

Cholamandalam MS Risk Services Limited,

India

Cholamandalam MS Risk Services Limited,

India Technip KT India

IOCL Marketing Terminal - Mathura



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LIST OF ABBREVIATIONS

ALARP : As Low as reasonably practicable

BLEVE : Boiling Liquid Expanding Vapor Explosion

CMSRS : Cholamandalam MS Risk Services Ltd.

IOCL : Indian Oil Corporation Limited

LOC : Loss of Containment Events

MOC : Material of Construction

QRA : Quantitative Risk Analysis

TPKTI : Technip KT India Ltd

UVCE : Unconfined Vapor Cloud explosion



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CONTENTS

LIST OF TABLES ............................................................................................................................ 5 EXECUTIVE SUMMARY ................................................................................................................. 6 CHAPTER 1 ..................................................................................................................................... 7 INTRODUCTION .............................................................................................................................. 7

1.1 INTRODUCTION ............................................................................................................................. 8 1.2 SCOPE OF STUDY ........................................................................................................................... 8 1.3 ABOUT THE CONSULTANTS ....................................................................................................... 9 1.4 METHODOLOGY ADOPTED ......................................................................................................... 9 1.5 ACKNOWLEDGMENTS ............................................................................................................... 10 1.6 DISCLAIMER................................................................................................................................ 10

CHAPTER 2 ................................................................................................................................... 11 FACILITIES DESCRIPTION .......................................................................................................... 11 CHAPTER 3 ................................................................................................................................... 15 QUANTITATIVE RISK ANALYSIS ................................................................................................ 15 INTRODUCTION ............................................................................................................................ 15

3.1 AN OVERVIEW ............................................................................................................................. 16 3.2 RISK CONCEPT ............................................................................................................................. 16 3.3 RISK ASSESSMENT PROCEDURE ............................................................................................. 17

CHAPTER 4 ................................................................................................................................... 20 RISK ASSESSMENT METHODOLOGY ....................................................................................... 20

4.1 IDENTIFICATION OF HAZARDS & RELEASE SCENARIOS .................................................. 21 4.2 FACTORS FOR IDENTIFICATION OF HAZARDS .................................................................... 21 4.3 TYPES OF OUTCOME EVENTS .................................................................................................. 23 4.4 CONSEQUENCE CALCULATIONS ............................................................................................. 25 4.5 SELECTION OF DAMAGE CRITERIA ........................................................................................ 27 4.6 PROBABILITIES ............................................................................................................................ 30

CHAPTER 5 ................................................................................................................................... 33 RISK ASSESSMENT ..................................................................................................................... 33

5.1 SCENARIO SELECTION ............................................................................................................... 34 5.2 ACCIDENT SCENARIOS FOR THIS PROJECT .......................................................................... 35 5.3 CONSEQUENCE RESULTS SUMMARY .................................................................................... 36 5.3.1 SUMMARY JET FIRE: ................................................................................................................... 36 5.3.2 SUMMARY LATE POOL FIRE: .................................................................................................... 36 5.3.3 SUMMARY BLEVE: ...................................................................................................................... 37 5.3.4 SUMMARY LATE EXPLOSION:.................................................................................................. 37 5.4 RISK PRESENTATION .................................................................................................................. 38

CHAPTER 6 ................................................................................................................................... 43 RISK CONTROL MEASURES ...................................................................................................... 43

6.0 PROPOSED RISK CONTROL MEASURES FOR THE PROJECT BY TECHNIP KT

INDIA ............................................................................................................................................. 44 CHAPTER 7 ................................................................................................................................... 45 RISK ACCEPTANCE ..................................................................................................................... 45

7.0 RISK ACCEPTANCE ..................................................................................................................... 46 CHAPTER 8 ................................................................................................................................... 48 REFERENCES ............................................................................................................................... 48

8.0 REFERENCES ................................................................................................................................ 49 CHAPTER 9 ................................................................................................................................... 50 ANNEXURES ................................................................................................................................. 50



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LIST OF TABLES

Table No 1: Effects Due To Incident Radiation Intensity .................................................................... 28

Table No 2: Damage Due To Overpressures ........................................................................................ 29

Table No 3: Wind direction .................................................................................................................. 31

Table No 4: Loss of Containment scenarios ......................................................................................... 34

Table No 5: Summary of Inputs and Possible outcomes: ..................................................................... 35

Table No 6: Summary Jet Fire.............................................................................................................. 36

Table No 7: Summary late explosion ................................................................................................... 37

Table No 8: Accident event frequency - Vessels.................................................................................. 38

Table No 9: Accident event frequency - Pipelines ............................................................................... 39

Table No 10: Risk Level Summary ...................................................................................................... 42



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EXECUTIVE SUMMARY

Indian Oil Corporation Limited (IOCL), the largest commercial undertaking in India, is

engaged in the business of refining, transportation and marketing of petroleum products.

IOCL, the Owner, intend to carry out revamp of the existing facilities of marketing terminal at

its Mathura Refinery in the State of Uttar Pradesh. Technip KT India Ltd (TPKTI), Noida has

been awarded the above project on EPCM basis. Cholamandalam MS Risk Services Limited

(CMSRS) was approached by Technip KT India Ltd (TPKTI) to carry out Quantitative Risk

Analysis (QRA) Study for the new facilities coming up in the marketing terminal. Accordingly

engineers from CMSRS had visited the site & offices of EPC companies to carry out the

study. Based on the site study and proposed document study potential scenarios, which can

cause significant consequences like fire, explosion etc were identified, and the

consequences of the scenarios were assessed using the software PHAST v6.6 and the Risk

levels were evaluated using PHAST Risk v6.6 developed by DNV.

The facility of interest has no scenario with higher risk value than the acceptable

level (1.0E-05/Avg Yr HSE UK New Nuclear power stations) with the present process

conditions, population distribution and whether condition. But however to maintain the risk

level below the acceptable levels the following should be strictly adhered to:

Proposed plant automation system should be implemented and maintained properly.

Periodical Inspection and thickness measurement of pipelines & storage tanks to be

done.

Ensure adherence to proposed risk control measures strictly.



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CHAPTER 1

INTRODUCTION



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1.0 PREFACE

1.1 INTRODUCTION

Indian Oil Corporation Limited (IOCL), the largest commercial undertaking in India, is

engaged in the business of refining, transportation and marketing of petroleum products.

IOCL, the Owner, intend to carry out revamp of the existing facilities of marketing terminal at

its Mathura Refinery in the State of Uttar Pradesh. Technip KT India Ltd (TPKTI), Noida has

been awarded the above project on EPCM basis. Cholamandalam MS Risk Services Limited

(CMSRS) was approached by Technip KT India Ltd (TPKTI) to carry out Quantitative Risk

Analysis (QRA) Study for the new facilities coming up in the marketing terminal. Accordingly

engineer from CMSRS had visited the IOCL office on 27th June, 2011 to collect the data for

the study. Based on the collected document the potential scenarios, which can cause

significant consequences like fire, explosion etc were identified, and the consequences of

the scenarios were assessed using the software PHAST v6.6 and the Risk levels were

evaluated using PHAST Risk v6.6 developed by DNV.

The purpose of the study includes the following:

To identify and assess those hazards and risks arising from their activities

connected to the Marketing terminal that requires management to comply with

regulatory requirements, company policy and business requirements.

To eliminate or reduce to As Low As Reasonably Practical (ALARP) in terms of risk

to human health, risk of injury, risk of damage to plant, equipment and environment,

business interruption or loss etc.

1.2 SCOPE OF STUDY

The scope of the QRA is given below:

- Identification of Hazards and Major Loss of Containment (LOC) events

- Calculation of physical effects of accidental scenarios, which includes

frequency analysis for incident scenarios leading to hazards to people and

facilities (flammable gas, fire, and smoke, explosion overpressure and toxic

gas hazards) and consequence analysis for the identified hazards covering

impact on people and potential escalation.



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- Damage limits identification and quantification of the risks and contour

mapping on the layouts.

- Individual risk quantification and contour mapping.

- Societal risk quantification and contour mapping

- Hazard mitigation recommendations based on QRA

The Indian Standard IS 15656: Code of practice - Hazard Identification and Risk Analysis

has been adopted for this study.

1.3 ABOUT THE CONSULTANTS

CMSRS is a joint venture between the Murugappa Group and Mitsui Sumitomo Insurance

Group of Japan. CMSRS offers specialized and innovative risk management solutions to

clients in India and rest of Asia. CMSRS has carried out more than 2200 assignments in the

field of risk management consultancy and training services across 32 industrial sectors

including refineries and petrochemical units. In addition to industrial sector and service

sector located in Kuwait, India, Hong Kong and Thailand, the Ministry of Environment and

Forests, Government of India and insurance companies located in India, Sri Lanka and

Singapore have been engaging the services of CMSRS to carry out a number of risk

analysis and specialized safety studies. The team members have wide experience in risk

management studies and have carried out studies for a number of industrial sectors

including refineries located in India and rest of Asia.

1.4 METHODOLOGY ADOPTED

Detailed data request for risk analysis study was submitted to the client before carrying out

site visit to familiarize the site officials on the nature of information that would be collected

during site visit. During site visit, CMSRS engineer had made a brief presentation to the site

officials on the objective, scope, methodology and deliverables of the risk analysis study.

Subsequently, site visit was carried out for the entire facility including railway wagon

decanting area to identify the potential hazard scenarios.

Then Risk Assessment calculations based on the collected data have been carried out at

CMSRS office using PHAST Risk Micro v6.6 software. Finally, risk reduction measures have

been suggested based on the risk levels.



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The above adopted methodology has been depicted in the form of flow chart below:

1.5 ACKNOWLEDGMENTS

Cholamandalam MS Risk Services gratefully acknowledges the co-operation received from

the management of IOCL and Technip KT India during the study. The CMSRSL team in

particular would like to thank the following for their support and help throughout the study:

1) Mr. Pradeep Saini, Manager, Marketing Terminal, Mathura Refinery, IOCL.

2) Mr. M. Sashisekar & Mr. Sameer Agarwal, Technip KT India.

1.6 DISCLAIMER

The advice rendered by CMSRS is in the nature of guidelines based on good engineering

practices and generally accepted safety procedures and CMSRS does not accept any liability for

the same. The priorities of suggestions shown in the report are advisory in nature and not binding

on the parties involved viz. CMSRS, TPKTI and IOCL

Introduction to the study

Site visit of the terminal to identify the hazards, scenarios for modeling, discussion with engineers and collection of information

Risk presentation and recommendations

Data input into Risk analysis software

Processing of risk analysis calculations and release

scenarios



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CHAPTER 2

FACILITIES DESCRIPTION



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2.0 FACILITIES DESCRIPTION

The existing and new additional facilities of the marketing terminal are detailed below.

LPG storage facility at Marketing Terminal

Existing LPG Storage at marketing terminal for loading in truck tankers

Remarks

No. of bullets 3 Excluding storage for bottling plant.

Capacity of each bullet, MT 1200

Total capacity of bullets, MT 3600

Total capacity of bullets, m3 6545

Storage available at marketing terminal with new capacity, days

2.3

No new additional storage capacity for LPG is required at marketing terminal as

confirmed.

Propylene storage facility at marketing terminal

Production Remarks

New Propylene Production, KMTPA 215

Propylene Production from refinery to marketing terminal, m

3/day

1222

Propylene Storage Facility at Marketing Terminal

Existing Propylene Storage at marketing terminal Remarks

No. of bullets 2

Capacity of each bullet, MT 200

Total capacity of bullets, MT 400

Total capacity of bullets, m3 784

Storage available at marketing terminal with new capacity, days

0.6 Not sufficient

New Propylene Storage proposed at marketing terminal

No. of bullets 1

Capacity of bullet, m3 1200

Total new + existing capacity, m3 1984

Storage available at marketing terminal with new capacity and new bullet, days

1.6



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Loading Bays

Propylene Remarks

New Propylene production, KMTPA 215

Existing Propylene Loading arms 3

Number of new propylene loading arms proposed

4

Total new capacity with 7 loading arms (considering 1 spare loading arm). MTPD

864

Considering 2 hrs loading time and 18 MT

capacity of a truck tanker.

Total new Annual loading capacity considering 300 working days, KMTPA

259

So, 4 Number of additional loading arms shall be sufficient for new Propylene loading capacity.

LPG Remarks

New LPG production to be loaded, KMTPA 530 Excluding LPG for

bottling plant (approx. 120KMTPA)

Existing LPG Loading arms 9

Number of new LPG loading arms proposed

6

Total new capacity with 15 loading arms (considering 2 spare loading arms). MTPD

1872

Considering 2 hrs loading time and 18 MT

capacity of a truck tanker.

Total Annual loading capacity considering 300 working days, KMTPA

561 considering 2 hrs loading

time per truck tanker

So, 6 Number of additional loading arms shall be sufficient for new LPG capacity.

Propylene & LPG loading facility (Pumps)

Propylene Pump Remarks

Number of existing propylene pump (1 operating + 1

spare)

Existing Propylene Pump Capacity, m3/hr

2 x 48

Proposed 2 new pump of capacity each 48 m3/hr

2 x 48

Total loading capacity with new and old pump,m3/hr

144 Considering 3 running pump



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LPG Pump Remarks

Number of existing LPG pump (1 operating + 1

spare)

Existing LPG Pump Capacity, m3/hr 2 x 150

Proposed 1(1 Operating) new pump of capacity 150 m3/hr

1 x 150

Total loading capacity with new and old pump,m3/hr

300



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CHAPTER 3

QUANTITATIVE RISK ANALYSIS

INTRODUCTION



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3.0 QUANTITATIVE RISK ANALYSIS – AN INTRODUCTION

3.1 AN OVERVIEW

Risk Analysis is proven valuable as a management tool in assessing the overall safety

performance of the Chemical Process Industry. Although management systems such as

engineering codes, checklists, and reviews by experienced engineers have provided

substantial safety assurances, major incidents involving numerous casualties, injuries and

significant damage can occur - as illustrated by recent world-scale catastrophes. Risk

Analysis techniques provide advanced quantitative means to supplement other hazard

identification, analysis, assessment, control and management methods to identify the

potential for such incidents and to evaluate control strategies.

The underlying basis of Risk Analysis is simple in concept. It offers methods to answer the

following four questions:

1. What can go wrong?

2. What are the causes?

3. What are the consequences?

4. How likely is it?

This study tries to quantify the risks to rank them accordingly based on their severity and

probability. The report should be used to understand the significance of existing control

measures and to follow the measures continuously. Wherever possible the additional risk

control measures should be adopted to bring down the risk levels.

3.2 RISK CONCEPT

Risk in general is defined as a measure of potential economic loss or human injury in terms

of the probability of the loss or injury occurring and magnitude of the loss or injury if it

occurs. Risk thus comprises of two variables; magnitude of consequences and the

probability of occurrence. The results of Risk Analysis are often reproduced as Individual

and groups risks and are defined as below.

Individual Risk is the probability of death occurring as a result of accidents at a plant,

installation or a transport route expressed as a function of the distance from such an activity.

It is the frequency at which an individual or an individual within a group may be expected to

sustain a given level of harm (typically death) from the realization of specific hazards.



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Such a risk actually exists only when a person is permanently at that spot (out of doors).

The exposure of an individual is related to

o The likelihood of occurrence of an event involving a release and

o Ignition of hydrocarbon,

o The vulnerability of the person to the event,

o The proportion of time the person will be exposed to the event (which is termed

'occupancy' in the QRA terminology).

The second definition of risk involves the concept of the summation of risk from events

involving many fatalities within specific population groups. This definition is focused on the

risk to society rather than to a specific individual and is termed 'Societal Risk'. In relation to

the process operations we can identify specific groups of people who work on or live close to

the installation; for example communities living or working close to the plant.

3.3 RISK ASSESSMENT PROCEDURE

Hazard identification and risk assessment involves a series of steps as follows:

Step 1: Identification of the Hazard

Based upon consideration of factors such as the physical & chemical properties of the fluids

being handled, the arrangement of equipment, operating & maintenance procedures and

processing conditions. External hazards such as third party interference, extreme

environmental conditions, aircraft / helicopter crash should also be considered.

Step 2: Assessment of the Risk

Arising from the hazards and consideration of its tolerability to personnel, the facility and the

environment. This involves the identification of initiating events, possible accident

sequences, and likelihood of occurrence and assessment of the consequences. The

acceptability of the estimated risk must then be judged based upon criteria appropriate to the

particular situation.

Step 3: Elimination or Reduction of the Risk

Where this is deemed to be necessary. This involves identifying opportunities to reduce the

likelihood and/or consequence of an accident.

Hazard Identification is a critical step in Risk Analysis. Many aids are available, including

experience, engineering codes, checklists, detailed process knowledge, equipment failure

experience, hazard index techniques, What-if Analysis, Hazard and Operability (HAZOP)

Studies, Failure Mode and Effects Analysis (FMEA), and Preliminary Hazard Analysis



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(PHA). In this phase all potential incidents are identified and tabulated. Site visit and study of

operations and documents like drawings, process write-up etc are used for hazard

identification.

Assessment of Risks

The assessment of risks is based on the consequences and likelihood. Consequence

Estimation is the methodology used to determine the potential for damage or injury from

specific incidents. A single incident (e.g. rupture of a pressurized flammable liquid tank) can

have many distinct incident outcomes (e.g. Unconfined Vapour Cloud Explosion (UVCE),

Boiling Liquid Expanding Vapour Explosion (BLEVE), flash fire.

PHAST v6.6 and PHAST Risk Micro v6.6

The software developed by DNV is used for risk assessment studies involving flammable

and toxic hazards where individual and societal risks are also to be identified. It enables the

user to assess the physical effects of accidental releases of toxic or flammable chemicals.

PHAST v6.6 is used for consequence calculations and PHAST Risk Micro v6.6 is used for

risk calculations. It contains a series of up to date models that allow detailed modeling and

quantitative assessment of release rate pool evaporation, atmospheric dispersion, vapour

cloud explosion, combustion, heat radiation effects from fires etc., The software is

developed based on the hazard model given in TNO Yellow Book as the basis.

Phast Risk v6.6 includes latest technical up gradation for carrying out modeling more

realistically which includes Unified dispersion modeling, Droplet modeling, CO2 modeling,

and Enhanced models for Long Pipeline Calculations to handle difficult compositions and

Time varying discharge enhancements to provide more realistic consequence and risk

results.

These software’s are developed based on the various incidents that had occurred over past

25 years. CMSRS has used the latest version of PHAST software for developing the

consequences and risks for each model.

Likelihood assessment is the methodology used to estimate the frequency or probability of

occurrence of an incident. Estimates may be obtained from historical incident data on failure

frequencies or from failure sequence models, such as fault trees and event trees. In this

study the historical data developed by software models and those collected by

CPR18E – Committee for Prevention of Disasters, Netherlands (Edition: PGS 3, 2005) are

used.



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Risk Assessment combines the consequences and likelihood of all incident outcomes from

all selected incidents to provide a measure of risk. The risk of all selected incidents are

individually estimated and summed to give an overall measure of risk.

Risk-reduction measures include those to prevent incidents (i.e. reduce the likelihood of

occurrence) to control incidents (i.e. limit the extent & duration of a hazardous event) and to

mitigate the effects (i.e. reduce the consequences). Preventive measures, such as using

inherently safer designs and ensuring asset integrity, should be used wherever practicable.

In many cases, the measures to control and mitigate hazards and risks are simple and

obvious and involve modifications to conform to standard practice. The general hierarchy of

risk reducing measures is:

Prevention (by distance or design)

Detection (e.g. fire & gas, Leak detection)

Control (e.g. emergency shutdown & controlled depressurization)

Mitigation (e.g. firefighting and passive fire protection)

Emergency response (in case safety barriers fail)



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CHAPTER 4

RISK ASSESSMENT METHODOLOGY



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4.0 RISK ASSESSMENT METHODOLOGY FOR PROSPOSED

INSTALLATION

4.1 IDENTIFICATION OF HAZARDS & RELEASE SCENARIOS

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

major releases from fractures of all storage tanks and connected pipelines. This compilation

includes all pipe work and vessels in direct communication, as these may share a significant

inventory that cannot be isolated in an emergency. The following data were collected to

envisage scenarios:

* Composition of materials stored in storage tanks / flowing through pipeline

* Inventory of materials stored in storage tanks / road tankers / railway wagons

* Flow rate of materials passing through pipelines

* Storage tanks / Pipeline conditions (phase, temperature, pressure)

* Connecting piping and piping dimensions.

Accidental release of flammable liquids / gases can result in severe consequences. Delayed

ignition of flammable gases can result in blast overpressures covering large areas. This may

lead to extensive loss of life and property. In contrast, fires have localized consequences.

Fires can be put out or contained in most cases; there are few mitigating actions one can

take once a flammable gas or a vapour cloud gets released. Major accident hazards arise,

therefore, consequent upon the release of flammable gases.

4.2 FACTORS FOR IDENTIFICATION OF HAZARDS

In any installation, main hazard arises due to loss of containment during handling of

flammable chemicals. To formulate a structured approach to identification of hazards, an

understanding of contributory factors is essential.

Blast over Pressures

Blast Overpressures depend upon the reactivity class of material and the amount of gas

between two explosive limits. For example MS once released and not ignited immediately is

expected to give rise to a vapour cloud. These vapours in general have medium reactivity

and in case of confinement of the gas cloud, on delayed ignition may result in an explosion

and overpressures.



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Operating Parameters

Potential vapor release for the same material depends significantly on the operating

conditions. This operating range is enough to release a large amount of vapor in case of a

leak / rupture, therefore the storage tank / pipeline leaks and ruptures need to be considered

in the risk analysis calculations.

Inventory

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

of release scenarios. Inventory plays an important role in regard to the potential hazard.

Larger the inventory of a vessel or a system, larger the quantity of potential release. A

practice commonly used to generate an incident list is to consider potential leaks and major

releases from fractures of pipelines and vessels/tanks containing sizable inventories.

Range of Incidents

Both the complexity of study and the number of incident outcome cases are affected by the

range of initiating events and incidents covered. This not only reflects the inclusion of

accidents and / or non-accident-initiated events, but also the size of those events. For

instance studies may evaluate one or more of the following:

o catastrophic failure of tank

o large hole (large continuous release)

o smaller holes (continuous release)

o leaks at fittings or valves (small continuous release)

In general, quantitative studies do not include very small continuous releases or short

duration small releases if past experience or preliminary consequence modeling shows that

such releases do not contribute to the overall risk levels.

Selection of Initiating Events and Incidents

The selection of initiating events and incidents should take into account the goals or

objectives of the study and the data requirements. The data requirements increase

significantly when non-accident-initiated events are included and when the number of

release size increase. While the potential range of release sizes is tremendous, groupings

are both appropriate and necessitated by data restrictions. The main reasons for including

release sizes other than the catastrophic are to reduce the conservatism in an analysis and

to better understand the relative contributions to risk of small versus large releases.



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As per Reference Manual Bevi Risk assessment version 3.2 only the Loss of Containment

(LOC) which is basically the release scenarios contributing to the individual and/ or societal

risk are included in the QRA. LOC scenarios for the New facilities of Marketing terminal are

included only if the following conditions are fulfilled:

Frequency of occurrence is equal to or greater than 10-9

and

Lethal damage (1% probability) occurs outside the establishment’s boundary or the

transport route.

There may be number of accidents that may occur quite frequently, but due to proper control

measures or fewer quantities of chemicals released, they are controlled effectively. A few

examples are a leak from a gasket, pump or valve, release of a chemical from a vent or

relief valve, and fire in a pump due to overheating. These accidents generally are controlled

before they escalate by using control systems and monitoring devices – used because such

piping and equipment are known to sometimes fail or malfunction, leading to problems.

On the other hand, there are less problematic areas / units that are generally ignore or not

given due attention. Such LOCs are identified by studying the facilities and suitable

techniques like Event Tree Analysis etc. and accidents with less consequence are ignored.

Some of the critical worst case scenarios identified by the Hazard Identification study are

also assessed as per the guidelines of Environment Protection Agency.

4.3 TYPES OF OUTCOME EVENTS

In this section of the report we describe the probabilities associated with the sequence of

occurrences which must take place for the incident scenarios to produce hazardous effects

and the modeling of their effects.

Considering the present case the outcomes expected are

- Jet fires

- Vapour Cloud Explosion (VCE)

- Late Pool Fire

Jet fires

Jet fire occurs when a pressurized release (of a flammable gas or vapour) is ignited by any

source. They tend to be localized in effect and are mainly of concern in establishing the

potential for domino effects and employee safety zones rather than for community risks.

The jet fire model is based on the radiant fraction of total combustion energy, which is

assumed to arise from a point slowly along the jet flame path. The jet dispersion model gives

the jet flame length.



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Vapour Cloud Explosion (VCE)

Vapour cloud explosion is the result of flammable materials in the atmosphere, a subsequent

dispersion phase, and after some delay an ignition of the vapour cloud. Turbulence is the

governing factor in blast generation, which could intensify combustion to the level that will

result in an explosion. Obstacles in the path of vapour cloud or when the cloud finds a

confined area, e.g. as under the bullets, often create turbulence. The VCE will result in

overpressures.

It may be noted that VCEs have been responsible for very serious accidents involving

severe property damage and loss of lives.

Pool fires

This represents a situation when flammable liquid spillage forms a pool over a liquid

or solid surface and gets ignited. Flammable liquids can be involved in pool fires where

they are stored and transported in bulk quantities.

Early pool fire is caused when the steady state is reached between the outflow of

flammable material from the container and complete combustion of the flammable material

when the ignition source is available. Late pool fires are associated with the difference

between the release of material and the complete combustion of the material

simultaneously. Late pool fires are common when large quantity of flammable material is

released within short time.

BLEVE (Boiling Liquid Expanding Vapour Explosion)

A BLEVE (Boiling Liquid Expanding Vapour Explosion) is simply explosively expanding

vapour or two-phase fluid. A BLEVE results from a “hot rupture” of a vessel typically

containing hydrocarbons such as LPG etc, stored and maintained as a liquid under

pressure, due to an impinging or engulfing fire. A flammable material will be ignited

immediately upon rupture by the impinging/engulfing fire and will burn as a fireball. A fireball

would also result from immediate ignition of a release resulting from cold catastrophic

rupture of a pressurized vessel. The initial phase of a gas pipeline rupture should also be

modelled as a fireball.

These outcome events are then further analyzed in the Risk estimation procedure.



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4.4 CONSEQUENCE CALCULATIONS

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.

Accidental release of flammable liquids can result in severe consequences. Immediate

ignition of the pressurized chemical will result in a jet flame. Delayed ignition of flammable

vapours can result in blast overpressures covering large areas.

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.

4.4.1 Source strength parameters

o Calculation of the outflow of liquid vapours out of a vessel / Tank or a pipe, in case

of rupture. Also two-phase outflow can be calculated.

o Calculation, in case of liquid outflow, of the instantaneous flash evaporation and of

the dimensions of the remaining liquid pool.

o Calculation of the evaporation rate, as a function of volatility of the material, pool

dimensions and wind velocity.

o Source strength equals pump capacities, etc. in some cases.

4.4.2 Consequential effects

o 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.

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

distance to the source.

o Energy of vapour cloud explosions [in bar], as a function of the distance to the

distance of the exploding cloud.

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

evaporated chemical. The latter can be either explosive or toxic.

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:

o Gas, vapour, liquid, solid?



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o Inflammable, explosive, toxic, toxic combustion products?

o Stored at high/low temperatures or pressure?

o Controlled outflow (pump capacity) or catastrophic failure?

The basic physical effect models consist of the following:

PROBABILITY OF INCIDENTS OCCURANCE



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4.5 SELECTION OF DAMAGE CRITERIA

The damage criteria give the relation between the extents of the physical effects (exposure)

and the effect of consequences. For assessing the effects on human beings consequences

are expressed in terms of injuries and the effects on equipment / property in terms of

monetary loss.

The effect of consequences for explosion or fire can be categorized as

Damage caused by heat radiation on material and people

Damage caused by explosion on structure and people

In Consequence Analysis studies, in principle three types of exposure to hazardous effects

are distinguished:

1 Heat radiation due to fires. In this study, the concern is that of Jet fires, pool fires

and BLEVE.

2 Explosions

3 Toxic effects, from toxic materials or toxic combustion products.

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

Following are the criteria selected for damage estimation:

Heat Radiation

The effect of fire on a human being is in the form of burns. There are three categories of

burn such as first degree, second degree and third degree burns. The consequences

caused by exposure to heat radiation are a function of:

o The radiation energy onto the human body [kW/m2

];

o The exposure duration [sec];

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



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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 No 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)

9.5 Pain threshold reached after 8 sec. second degree burns after

20 sec.

12.5 Minimum energy required for piloted ignition of wood, melting

plastic tubings etc.

37.5 Heavy Damage to process equipments

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. 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. 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.

Assumptions made for the study (As per the guidelines of CPR 18 E Purple Book)

The lethality of a jet fire is assumed to be 100% for the people who are caught in the

flame. Outside the flame area, the lethality depends on the heat radiation distances.

For the flash fires lethality is taken as 100% for all the people caught outdoors and

for 10% who are indoors within the flammable cloud. No fatality has been assumed

outside the flash fire area.



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Explosion

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

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

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

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

A peak overpressure of 0.1bar 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 No 2: Damage Due To Overpressures

Peak Overpressure Damage Type Description

0.30 bar Heavy Damage Major damage to plant equipment

structure

0.10 bar Moderate Damage Repairable damage to plant equipment &

structure

0.03 bar Significant Damage Shattering of glass

0.01 bar Minor Damage Crack in glass

Assumptions for the study (As per the guidelines of CPR 18 E Purple Book)

Overpressure more than 0.3 bar corresponds approximately with 50% lethality.

An overpressure above 0.2 bar would result in 10% fatalities.

An overpressure less than 0.1 bar would not cause any fatalities to the public.

100% lethality is assumed for all people who are present within the cloud proper.



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4.6 PROBABILITIES

4.6.1 Population Probabilities

It is necessary to know the population exposure in order to estimate the consequences and

the risk resulting from an incident. The exposed population is often defined using a

population density. Population densities are an important part of a QRA for several reasons.

The most notable is that the density is typically used to determine the number of people

affected by a given incident with a specific hazard area. Sometimes, population data are

available in sketchy forms. In the absence of specific population data default categories can

be used.

The population density can be averaged over the whole area that may be affected or the

area can be subdivided into any number of segments with a separate population density for

each individual segment.

In this study, based on the discussions with IOCL and Technip officials, the following

population data were considered for the study for the habitations located in the vicinity of the

facility. Layout showing the population detail is attached as Annexure 01.

Population detail

Admin building – 35 people

Main Gate – 5 people

TLF loading – 40 people

New LPG loading – 15 people

Pump house – 2 people

Rest room – 15 people

Internal Gate – 3 people

Inside parking – 2 people

4.6.2 Failure / Accident Probabilities

The failure data is taken from CPR 18E –Guidelines for Quantitative Risk Assessment,

developed by the Committee for the Prevention of Disasters, Netherlands.

Specific details of failure probabilities are detailed in section 5.4



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4.6.3 Weather Probabilities

Based on the available climatologically tables and other meteorological data, the following

data is compiled.

Table No 3: Wind direction

The above data has been considered for determining the pre-dominant wind direction for

modeling the scenarios for the present study.

Wind velocity

As per the standard meteorological data available for this site, wind velocity varies between

1.5 m/s and 5 m/s and the same has been taken for this study.

WIND DIRECTION

Month N NE E SE S SW W NW CALM

Jan I 1 2 1 1 1 3 4 7 80

II 1 6 1 2 0 4 4 15 67

Feb I 1 2 1 1 1 5 5 8 76

II 2 7 1 1 0 6 5 21 57

Mar I 1 2 2 2 2 4 2 7 78

II 1 6 1 2 0 5 5 27 53

Apr I 1 2 0 2 2 4 4 7 78

II 1 3 0 1 0 10 5 31 49

May I 1 1 1 2 2 7 4 8 74

II 1 5 1 2 1 10 6 27 47

June I 1 3 3 4 2 10 7 6 64

II 2 9 3 3 2 13 6 16 46

July I 0 3 4 4 2 9 2 2 74

II 1 10 5 6 1 13 2 6 56

Aug I 0 2 2 2 1 8 2 2 81

II 1 10 2 5 2 12 2 6 60

Sept I 0 2 2 3 0 4 3 2 84

II 1 8 3 4 2 6 2 9 65

Oct I 0 1 0 2 1 2 1 2 91

II 0 5 1 1 0 1 2 9 81

Nov I 0 1 1 1 0 1 1 3 92

II 0 1 0 0 0 0 1 7 91

Dec I 0 1 1 1 1 2 1 4 89

II 0 3 0 1 0 1 2 9 84

Average

Avg I

0.50 1.83 1.50 2.08 1.25 4.92 3.00 4.83 80.08

Avg II

0.92 6.08 1.50 2.33 0.67 6.75 3.50 15.25 63.00



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Stability Class

For this study, the following two weather stability classes are considered:

1.5 F (Where F denotes Stable Condition – night with moderate clouds and light

moderate winds; 1.5 denotes wind velocity in m /sec)

5.0 D (where D denotes neutral condition – little sun and high wind or over cast /

windy night; 5.0 denotes wind velocity in m /sec)

Temperature & Humidity

The Mean Daily Max Air Temperature is 32.4°C. The Annual mean % humidity is 61.92%.

4.6.4 Ignition Probabilities

For hydrocarbon releases from the storage/ handling system, where a large percentage of

rupture events may be due to third party damage, a relatively high probability of immediate

ignition is generally used.

Delayed ignition takes other factors into account. Delayed ignition probabilities can also be

determined as a function of the cloud area or the location. In general as the size of the cloud

increases, the probability of delayed ignition decreases. This is due to the likelihood that the

cloud has already encountered an ignition source and ignited before dispersing over a larger

area (i.e. the cloud reaches an ignition source relatively close to the point of origin).

For this study the ignition probabilities have been modified to suit the existing site conditions.

The ignition probabilities inside enclosed areas shall be much higher than the open areas. It

is because of the fact that there will be much more activities taking place and the possibility

of ignition increases.

In this study the following probabilities were taken as per CPR 18 E

Ignition probability for this site : 0.5

4.7 EXPOSURE TO NATURAL HAZARDS

4.7.1 Earthquake

As per the Hazard Vulnerability Atlas, Mathura, Uttar Pradesh falls under Zone III –

Moderate damage Risk Zone (MSK VIII).

4.7.2 Storm / Cyclone

As per the Hazard Vulnerability Atlas, Mathura, Uttar Pradesh falls under High Damage Risk

Zone – B (Vb – 47 m/sec).



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CHAPTER 5

RISK ASSESSMENT



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5.0 CONSEQUENCE ANALYSIS

5.1 SCENARIO SELECTION

This section documents the consequence-distance calculations, which have been computed

for the accident release scenarios considered.

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

high frequency - low outcome events are distinguished. For this study, LOC scenarios were

selected for modeling.

While estimating the consequences only passive control measures were considered

as per CPR 18 E guidelines. The base frequency taken for the scenario does not give

credit for active control measures.

Following are the potential Loss of Containment scenarios envisaged for the Proposed New

facilities in marketing terminal.

Table No 4: Loss of Containment scenarios

S No SCENARIO

1. Leak of (150-V-103) propylene Mounded bullet

2. Rupture of (150-V-103) propylene Mounded bullet

3. Leak of LPL-1122-BD-250 pipeline from LPG loading pumps to loading bays

4. Rupture of LPL-1122-BD-250 pipeline from LPG loading pumps to loading bays

5. Leak of PRL-1121-BD-150 pipeline from propylene loading pumps to loading bays

6. Rupture of PRL-1121-BD-150 pipeline from propylene loading pumps to loading bays

The base frequency probability for each event and ignition probability are taken from

Guidelines for Quantitative Risk Assessment CPR 18 E (Purple book), Committee for the

Prevention of Disasters, Netherlands

5.2 ACCIDENT SCENARIOS FOR THIS PROJECT

Sudden release of hydrocarbon can result in a number of accident situations. As large number of failure cases can lead to the same type of

consequences, representative failure cases are selected for this analysis. The failure cases are based on conservative assumptions and

engineering judgment. Typically, failure models are considered for 100% pipe diameter/ catastrophic rupture of vessels for rupture and 10% leak

(Hole Size Max 50mm) based on the guidelines of CPR 18 E.

Table No 5: Summary of Inputs and Possible outcomes:

Tanks:

S.No Scenarios Material handled

Quantity Pressure kg/cm

2

Temp °C

Height / Dia

M

Dia/ Length

M Jet Fire

Late pool fire

VCE

1 Leak of (150-V-103) propylene Mounded bullet

propylene 600 MT 20.5 Amb 7 35 Applicable Not

Applicable Applicable

2 Rupture of (150-V-103) propylene Mounded bullet

propylene 600 MT 20.5 Amb 7 35 Not

Applicable Not


Pipelines:

S. No

Scenarios Material Flow Rate m3/hr

Operating Pressure (Kg/cm2)

Operating Temp in

C

Dia of Pipeline

‘In’

Length of

pipeline Jet fire

Late Pool Fire

VCE

3 Leak of LPL-1122-BD-250 pipeline from LPG loading pumps to loading bays

LPG 300 5 - 14.5 2 - 48 8 15 Applicable Not


4 Rupture of LPL-1122-BD-250 pipeline from LPG loading pumps to loading bays

LPG 300 5- 14.5 2 - 48 8 15 Applicable Not


5 Leak of PRL-1121-BD-150 pipeline from propylene loading pumps to loading bays

Propylene 144 5 - 23 2 - 48 6 265 Applicable Not


6 Rupture of PRL-1121-BD-150 pipeline from propylene loading pumps to loading bays

Propylene 144 5- 23 2 - 48 6 265 Applicable Applicable Applicable

The composition for LPG is given as Annexure no 02

5.3 CONSEQUENCE RESULTS SUMMARY

5.3.1 SUMMARY JET FIRE:

Table No 6: Summary Jet Fire

S. No Scenarios

Damage Downwind Distances in m

1.5F 5D

4 12.5 37.5 4 12.5 37.5

kW/m2 kW/m

2

1 Leak of (150-V-103) propylene Mounded bullet

22 9 NR 22 13 6


NA NA NA NA NA NA

3 Leak of LPL-1122-BD-250 pipeline from LPG loading pumps to loading bays

67 54 45 60 45 37


497 389 324 417 315 254


51 41 35 44 34 28


187 150 128 165 126 103

Legend:

NR = Not Reached

NA = Not Applicable

Analysis:

Rupture of LPL-1122-BD-250 pipeline from LPG loading pumps to loading bays will cause the

maximum damage. The equipment within a distance of 497 m may be subjected to major damage.

The piloted ignition of wood, melting of plastics tubing’s etc is possible within the distance of 389 m.

First degree burns may be caused for persons who are within 324 m distance.

5.3.2 SUMMARY LATE POOL FIRE:

The material released to the atmosphere from the process vessel in case of a leak/ catastrophic

rupture is in gaseous state, formation of pool is not possible. Therefore Late Pool fire scenario don’t

apply for the scenario under study.



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5.3.3 SUMMARY BLEVE:

BLEVE has been considered for the study. Considering the Material, quantity of release, Weather

Condition & other process parameters, BLEVE does not arise.

5.3.4 SUMMARY LATE EXPLOSION:

Table No 7: Summary late explosion

S. No Scenarios

Damage Downwind Distances in m

1.5F 5D

0.03 0.1 0.3 0.03 0.1 0.3

bar bar

1. Leak of (150-V-103) propylene Mounded bullet NR NR NR NR NR NR

2. Rupture of (150-V-103) propylene Mounded bullet 2021 971 584 2048 1000 686


175 138 124 144 113 102


621 474 450 671 546 523


108 86 78 93 74 67


397 286 248 434 346 328

Legend: NA= Not Applicable NR = Not Reached

Analysis:

Rupture of (150-V-103) propylene Mounded bullet will cause Significant damage, Moderate and

heavy damage to the surrounding area and shattering of glasses may take place within the distance

of 2048 m. Repairable damage to plant equipment and structure may be caused with the distance of

1000 m. Major equipment damage may be caused with in the distance of 686 m.



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5.4 RISK PRESENTATION

Individual Risk and Societal Risk:

The individual risks are calculated based on base event frequency, ignition probability, population

density in the area etc. The accident event frequency details for this study are taken from Purple

Book (CPR 18 E) are given below.

The event Frequencies are as follows (As per Bevi Manual)

For calculating the frequency of Vessel to be applied for modeling the following factors are taken

assumed

The Vessels/ tanks are designed as per standards

Corrosion protection for the vessels is accounted for in the design

Material of Construction of vessels is suitable for the process conditions

Table No 8: Accident event frequency - Vessels

S.No Scenarios Basic

Failure Frequency

Safety Instrumented System

Fire Protecti

on system

Calculated failure

Frequency Temperature

Level Pressure


1.00E-05 0.99 0.99 0.99 0.4 3.88E-06


5.00E-07 0.99 0.99 0.99 0.4 1.94E-07

For calculating the frequency of pipelines to be applied for modeling the following factors are taken

into consideration

1. Blocking systems :

The blocking systems are used to limit the released quantity following a LOC. A blocking system

consists of a detection system (ex; gas detection, hydrocarbon detection, etc) combined with shut-off

valves. The shut-off valves can be closed automatically or manually. Blocking systems are further

classified into Automatic (0.001), semi-automatic (0.01) & non-automated (Manual) (0.99) system. In

the present case, blocking system is non-automated (manual) system, since no detection system is

available.



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2. Fire suppression systems

The fire protection systems & fire fighting facilities which are used to restrict fire, the various

factors affecting the fire protection systems as per “Thomas F Barry, Risk Informed Performance

Based Fire Protection System – An Alternative to Prescriptive Codes” are:

Response effectiveness (i.e. the system is responsive to a specific scenario) - In this case,

responsiveness can be questioned since, its manual operation. (Max. Credit can be around

33.33%)

On-line availability (i.e. the system is online at the time of the emergency) - As per the site

visit data, the FPS system is charged always (Max. credit can be 33%)

Operational reliability (the system functions properly at the time of emergency) - As per the

site visit, the FPS is maintained regularly (Max. credit can be around 33%)

The other safety system which have been considered in evaluating the failure frequency as per BEVI

manual are

3. Excess Flow check valve (EFCV)

4. Non Return Valve (NRV)

Table No 9: Accident event frequency - Pipelines

S. No

Scenarios

Basic Failure

Frequency per year

Blocking System

NRV EFCV

Fire Protecti

on system

Total Failure

Frequency


7.50E-06 0.01 0.06 0.99 0.4 1.78E-09


1.50E-06 0.01 0.06 0.99 0.4 3.56E-10


1.33E-04 0.01 0.06 0.99 0.4 3.15E-08


2.65E-05 0.01 0.06 0.99 0.4 6.30E-09

Risk Level Presentation of scenarios


Individual Risk /Avg Yr: 4.02E-06



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Societal Risk/ Avg Yr: 3.75E-06

Table No 10: Risk Level Summary

S. No Scenarios IR

SR Overall Admin Boundary


Negligible Negligible Negligible Negligible


4.02E-06 2.95E-08 6.34E-08 3.75E-06









NOTE: Negligible represents a Risk value equal to or below 1.0E-08/Avg Yr.



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CHAPTER 6

RISK CONTROL MEASURES



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6.0 PROPOSED RISK CONTROL MEASURES FOR THE PROJECT BY TECHNIP KT INDIA

Fire Water Network

The fire water protection system is designed as per OISD standards

The mounded bullet , pumps, bays are provided with deluge valve and sprinkler system as

per codes

Fire water monitors

Double headed hydrants

Instrumentation available

All the valves are fire safe type

ROV status indication is made available in control room and field

Safety valve discharge for bullet is vented vertically upwards to atmosphere at min elevation

of 3 m from top of the highest platform in the radius of 50 m



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CHAPTER 7

RISK ACCEPTANCE



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7.0 RISK ACCEPTANCE

In India, there are no defined criteria for risk acceptance. However, in IS 15656 – Code of Practice

for Hazard Identification and Risk Analysis, Annexure E summarizes the risk criteria adopted in

some countries. Extracts for the same is presented below:

RISK CRITERIA IN SOME COUNTRIES

Authority and Application Maximum Tolerable Risk

(per year) Negligible Risk

(per year)

VROM, The Netherlands (New) 1.0E-6 1.0E-8

VROM, The Netherlands (existing) 1.0E-5 1.0E-8

HSE, UK (existing-hazardous industry) 1.0E-4 1.0E-6

HSE, UK (New nuclear power station) 1.0E-5 1.0E-6

HSE, UK (Substance transport) 1.0E-4 1.0E-6

HSE, UK (New housing near plants) 3*1.0E-6 3*1.0E-7

Hong Kong Government (New plants) 1.0E-5 Not used

To achieve the above risk acceptance criteria, ALARP principle was followed while suggesting risk

reduction recommendations

Unacceptable region 10

-5 Per annum

Risk cannot be justified

The ALARP or tolerability Region (risk is undertaken only if a benefit is desired)

Tolerable only if further risk reduction is impractical, or the cost is not proportionate to the benefit gained

Broadly acceptable region Negligible risk

Risks closer to the unacceptable region merit a closer examination of potential risk reduction measures



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Based on the guidelines the following are the scenarios of the proposed facilities of marketing

terminal, falls under the category where the risk are above the acceptable level (1.0E-05 per Avg Yr

HSE UK New Nuclear power stations).

As there is no scenario which has a value greater than the acceptable level, the risk posed due to

revamping of facilities in marketing terminal to the population in and around the plant are well within

the acceptable level. But however to see that the risk is kept in the acceptable levels the following

should be strictly adhered to:

Proposed plant automation system should be implemented and maintained properly.

Periodical Inspection and thickness measurement of pipelines & storage tanks to be done.

Ensure adherence to proposed risk control measures strictly.



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CHAPTER 8

REFERENCES



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8.0 REFERENCES

8.1 IS 15656:2006 - Hazard identification and risk analysis - Code of practice Guidelines

for Quantitative Risk Assessment CPR 18 E (Purple book), Committee for the

Prevention of Disasters, Netherlands (Edition : PGS 3, 2005)Guidelines for Hazard

Evaluation Procedures, Center for Chemical Process Safety, American Institute of

Chemical Engineers, New York, New York, 1992.

8.4 ASME 31.4:2006 - Pipeline Transportation Systems for Liquid Hydrocarbons and

other Liquids



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CHAPTER 9

ANNEXURES

List of Annexure

Annexure No 01: Layout showing the population details

Annexure 02: LPG Composition

CRACKED LPG

Sl. No Component Unit Composition

1 METHANE wt% 0.0000

2 ETHANE wt% 0.0000

3 PROPYLENE wt% 0.7582

4 PROPANE wt% 8.4514

5 1BUTENE wt% 59.556

6 T2PENTENE wt% 0.0439

7 C2PENTENE wt% 0.0198

8 IBUTANE wt% 23.726

9 BUTANE wt% 6.0601

10 IPENTANE wt% 1.0095

11 PENTANE wt% 0.0304

12 12BUTADIENE wt% 0.0000

13 H2S ppmw 0.0000

14 ETSH ppmw 2.0000

15 CH4S ppmw 6.0000

16 ETHYLENE wt% 0.0000

17 METHYL ACETYLENE ppmw 0.0000

18 PROPADIENE ppmw 0.0000

19 13BUTADIENE wt% 0.0000

20 CO ppmw 0.0000

21 H2O wt% 0.0000

22 CO2 ppmw 0.0000

23 O2 ppmw 0.0000

24 COS ppmw 0.0000

25 AMMONIA ppmw 0.0000

26 HYDRO CHLORIDE ppmw 0.0000

27 SULFUR DIOXIDE ppmw 0.0000

28 HCN ppmw 0.0000

29 2M1BUTENE wt% 0.1009

30 2M2BUTENE wt% 0.0254

31 3M1BUTENE wt% 0.1366

32 1PENTENE wt% 0.0665

33 CYCLO PENTANE wt% 0.0002

34 ISOPRENE (2 METHYL-1,3-BUTADIENE) wt% 0.0036

35 CD13 (CYCLOPENTADIENE) wt% 0.0101

36 PHOSPHINE ppbw 0.0000

37 ARSINE ppmw 0.0000

38 TOTAL ARSENIC ppbw 0.0000

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