Process Plant Safety

CHE F413CHE F413

Text Books:

T1: Crowl D.A., and Louvar J.F., Chemical Process Safety:

Fundamentals with Applications, Pearson Education,

India 3ed , 2013.

T2: Fulekar M.H., Industrial Hygiene and Chemical

Safety, I.K. International, New Delhi, 2006.

BOOKS

Safety, I.K. International, New Delhi, 2006.

Reference Books:

R1: Sanders R.E., Chemical Process Safety: Learning from

case Histories, Butterworth-Heinemann, An imprint of

Elsevier, Boston, 2007.

R2: K.S.N.Raju, Chemical Process industry safety, Tata-

McGraw Hill Pub, 2014

R3: Loss Prevention Hazard Idenitification, Assessment

and Control Volume 1-3 by Frank P Lees, B-H publication

EC No.

Evaluation Component

Duration(min)

Weightage

Date & Time Nature of Exam

1. Test I 60 25 22nd Feb (4-5 PM)

CB

2. Test II 60 25 28th Mar(4-5 PM)

OB

Safety-Evaluation Scheme

3. Attendance/Quiz>85%80-85%70-80

Safety-Overall CourseTopics :

1.Introduction

2.Toxicology

3.Industrial hygiene

4.Source models

5.Dispersion models5.Dispersion models

6.Fire and Safety models-Flammability

diagrams

7.Hazard identification, HAZOP

8.Risk assessment

9.Relief concepts-types

10.Onsite, Off site emergency and safety audit

Introduction to Safety

The chemical industry more complex

processes, high pressure, more reactive and exotic

chemistry

More complex process requires complex safety

technology which leads to chemical engineers technology which leads to chemical engineers

need a more detailed and fundamental

understanding of safety.

Safety is equal in important to production and

has developed into a scientific discipline

Introduction to Safety Continue

Examples of the technology of safety

include

Dispersion models representing the

spread of toxic vapor through a plant spread of toxic vapor through a plant

after a release.

Mathematical technique to determine

the various ways that process can fail,

and the probability of failure

Introduction to Safety Continue

The word safety older strategy

accident prevention by using hard

hats, safety shoes, and variety of

rules and regulation.

Now replaced by loss prevention

which includes hazard identification ,

technical evaluation, and the design

of new engineering feature to prevent

loss

Three important terminologies

Safety or loss prevention the prevention of accident through the use of appropriate technologies to identify the hazards of a chemical plant and eliminate them before accident occurs

Hazard a chemical or physical condition that has Hazard a chemical or physical condition that has the potential to cause damage to people, property or the environment

Risk a measure of human injury, environmental damage or economic loss in terms of both the incident likelihood and the magnitude of the loss or injury

Three important terminologies-Cont

Chemical plants contain a large variety of hazards.

There are the usual mechanical hazards that cause There are the usual mechanical hazards that cause worker injuries from tripping, falling or moving equipment

There are chemical hazard includes Fire and explosion hazards, reactivity hazards and toxic hazards.

Safety Programs

A successful safety program requires several ingredients. System Attitude Fundamentals Experience Time You

Safety Programs-Contd

System: the program needs a system:

To record what needs to be done to have an outstanding safety program

To do what needs to be done.

To record that the required tasks are done. To record that the required tasks are done.

Attitude:

The participants must have a positive attitude. This includes willingness to do some of the thankless work that is required for success.

Safety Programs-Contd

Fundamentals

The participants must understand and use the fundamentals of chemical process safety in the design, construction and operation of their plants.

ExperienceExperience

Everyone must learn from the experience of history or doomed to respect it. Read and understand the case histories of past

accidents

Ask people in their own and other organizations for their experience and advice.

Safety Programs-Contd

Time

Everyone should recognize that safety takes time.

This includes time to study, time to do the work, record results, share experience and to train or be trained.

YouYou

Everyone should take the responsibility to contribute to the safety program.

A safety program must have the commitment from all levels within the organisation.

Importance equal to production.

Accident and loss statistics It measures the effectiveness of safety program.

Whether process is safe or safety procedure is working effectively.

Many statistical methods are available but must be used carefully.

Like most statistics are only averages and do not reflect the potential for single episodes involving substantial losses.substantial losses.

No single method is capable of measuring all required aspects.

The three systems to be considered are OSHA incidence rate

Fatal Accident Rate (FAR)

Fatality rate or deaths per person per year

Accident and loss statistics-ContdOSHA

Occupational safety and Health Administration

OSHA is responsible for ensuring safe working environment.

OSHA incidence rateOSHA incidence rate

It is based on cases per 100 worker years. A worker yearassumed to contain 2000 hours (50 work weeks/yr x 40

hrs/week).

It is calculated from the Number of occupational injuriesand illness and the total number of employee hours workedduring the applicable period.

Accident and loss statistics-Contd

Accident and loss statistics-Contd

OSHA incidence rate

It provides information on all types of work

related injuries and illness , including fatalities.

It provides better representation than system It provides better representation than system

based on fatalities alone.

For instance , a plant might experience many

small accident with resulting injuries , but no

fatalities.

Accident and loss statistics-Contd

Fatal Accident Rate (FAR)

It report number of fatalities based on 1000

employee working their entire lifetime.

The employee assumed to work a total of 50

years. So FAR based on 108 working hours

Accident and loss statistics-Contd

Fatality Rate

The fatality rate or deaths /person/year is

independent of the no of hours worked and it

report only the no of fatalities

expected/person/yrexpected/person/yr

Accident and loss statistics-Contd

Accident and loss statistics-ContdRecognizing that the chemical industry is safe,

why is there so much concern about chemical

plant safety?

The concern has to do with the industry's The concern has to do with the industry's

potential for many deaths, as, for example, in

the Bhopal, India, tragedy.

Accident statistics do not include information

on the total number of deaths from a single

incident. Accident statistics can be somewhat

misleading in this respect.

Accident and loss statistics-ContdFor example, consider two separate chemical plants.

Both plants have a probability of explosion and complete

devastation once every 1000 years.

The first plant employs a single operator. When the plant

explodes, the operator is the sole fatality. The second plant explodes, the operator is the sole fatality. The second plant

employs 10 operators. When this plant explodes all 10

operators succumb.

In both cases the FAR and OSHA incidence rate are the

same; the second accident kills more people, but there are

a correspondingly larger number of exposed hours.

In both cases the risk taken by an individual operator is

the same

Nature of the Accident process

Fires are the most common, followed by explosion

and toxic release.

With respect to fatalities, the order reverses, with

toxic release having the greatest potential for

fatalities

Nature of the Accident process

Types of loss in largest chemical plant accidents

Engineering Ethics

Engineers are responsible for minimizing losses

and providing a safe and secure environment for

the company's employees.

Engineers have a responsibility to themselves, Engineers have a responsibility to themselves,

fellow workers, family, community, and the

engineering profession.