SAFETY AND HEALTH IN CHEMICAL INDUSTRYSKF4163

SYED ANUAR FAUA’AD B. SYED MUHAMMADDept. of Bioprocess and Polymer Engineering,

Faculty of Chemical Engineering.N01-257

syed@utm.my07 – 55 35484

Notes contributor: Mohd. Fadhil/Tn. Amran

•Official Bike Laws in Japan

With a few notable exceptions, cyclists are required to follow the same traffic rules

as drivers.

Basic rules of the Road

Cyclists ride on the left hand side of the road.

•Riding dangerously, failing to stop at a stop light, or riding with broken brakes

carries a maximum penalty of a ¥500,000 fine and/or three months in prison.

•Biking under the influence of alcohol is forbidden and carries a maximum penalty

of five years in prison and a ¥1,000,000 fine.

•Cycling on sidewalks is forbidden, except where indicated by shared sidewalk

signs.

•

An overview of traffic law as well as a guide to Japanese traffic signs can be

found here (pdf). Alternately, there is a very thorough guide to the rules of the

road that can be purchased through the Japanese Automobile Foundation.

Other Bicycle Laws

Riding while carrying an umbrella, listening to an iPod, or talking on the phone are

prohibited; violators can face a fine of up to ¥500,000

•All bikes are required to have a bell and a headlamp (if riding at night)

•It is illegal to ride tandem bicycle (except in Nagano)

•Also illegal (and in line with the previous): riding with a passenger (with the

exception of a child below the age of six). Double riders could face a ¥500,000

fine

•A cyclist may carry one child under the age of six in a designated child seat

•Children under the age of 13 years must wear a bike helmet

•Bicycles must be registered in the owner’s name at the prefectural police

department

Tandem Bicycle

Cycle safety in FRANCERoads are shared by motorists and cyclists, which means that there must be mutual respect between road users.Cyclists, the same as drivers, must adhere to the highway code which guarantees the safety of oneself and all road users. To cycle in complete safety, all cyclists must have a well-equipped bike in good condition. Above all, cyclists must know and apply basic rules of road safety, in built up areas and in the countryside, during the day and at night.The equipmentA well-equipped bike in good condition contributes to your safety on the road as well as the safety of other road users.Obligatory equipment:•Two brakes, front and rear

•A yellow or white light on the front of your bike and a red light at the back.

•A horn, bell or way of attracting attention.

•Reflectors: red at the back, white at the front, orange on the sides and on the pedals.

•All cyclists (and passengers) on the road at night or in poor visibility,

• outside of built-up areas must wear a reflective vest.

Basic safety rulesIn built-up areas•Cycle on the right-hand side of the road, 1 metre from the pavement and from parked cars.

•Be bold and maintain your cycling line in the road if it would be dangerous for a car to overtake you.

•Use cycle paths where possible.

•Keep a safe distance of 1 metre from other vehicles.

•Don’t zig-zag between cars.

•At junctions, pull slightly forward of other vehicles so that you can be seen.

•Be wary of car doors which can open suddenly and of children who can jump out from between 2 vehicles.

•Don’t cycle on the pavement. Only children of less than 8 years old are allowed to cycle their bikes on the pavement.

•In pedestrian-priority zones, don’t cycle faster than 20km/h and respect the pedestrian’s priority.

•In zones where the speed is limited to 30 and in pedestrian-priority zones, bikes can cycle in both directions. This allows you to benefit from a greater visibility and to avoid

main roads and junctions and make your journey simpler.

On the road•Don’t cycle too close to the sides of the road, to avoid ruts and gravel.

•When cycling around corners, keep to the right as cars will only see you at the last minute.

•Be especially careful when a lorry drives past: the air vacuum might destabilise you and make you lost balance.

•If you are cycling in a group, cycle 2 abreast or in single file. At night, if a vehicle wishes to overtake or if the circumstances make it necessary (narrow roads etc), then you

should cycle systematically in single file.

•If your group is larger than 10 people, you should split into smaller groups.

Don’t forget !- Don’t transport a passenger, except on a fixed seat on a bike. If the passenger is less than 5 years old, this passenger seat should be equipped with foot-rests and straps.- At a junction, never position yourself at the side of a lorry or bus in their blind-spot. Make yourself seen.- The highway code applies to cyclists as it applies to all road users. Any violation or infringement can receive a fine.- In the case of rain, increase your safety distance and be careful when vehicles overtake you.

Bicycle Safety Tips for Bicycling in New York (Produced by Department of Transport, N.Y)Bicycle safety tips intended to minimize crashes and injuries while bicycling include:•Obey traffic signs and signals - Bicycles must follow the rules of the road like other vehicles.•Always wear your helmet - Bicyclist's 14 years old and younger are required to wear a helmet when operating a bicycle. The helmet must conform to the standard established by the American National Standard Institute (ANSI), the American Society for Testing and Materials (ASTM) or Snell Memorial Foundation (Snell) at all times.•Never ride against traffic - Motorist’s aren't looking for bicyclists riding on the wrong side of the road. State law and common sense require that bicyclists drive like other operating vehicles.•Don’t pass on the right - Motorist's may not look for or see a bicycle passing on the right.•Keep both hands ready to brake - You may not stop in time if you brake one-handed. Allow extra distance for stopping in the rain, since brakes are less efficient when wet.•Scan the road behind you - Learn to look back over your shoulder without losing your balance or swerving. Some riders use rear-view mirrors.•Never operate a bicycle wearing headphones, talking on a cell phone or text messaging - Wearing headphones, talking on a cell phone or text messaging when operating a bicycle can be a deadly distraction. Be alert to your surroundings; stop your bicycle when sending or receiving a cell phone call or text message. •Follow lane markings - Don't turn left from the right lane. Don't go straight in a lane marked “right-turn only.”•Do not consume alcohol - Consuming alcohol and operating a bicycle do not mix. Alcohol can dramatically diminish a bicyclist’s cognitive and physical abilities and can result in a crash.•Dress appropriately - In rain, wear a poncho or a waterproof suit. Dress in layers so you can adjust to temperature changes. Wear brightly colored clothing.•Use hand signals - Hand signals tell motorists and pedestrians what you intend to do. Signal as a matter of law, of courtesy and of self-protection.•Ride in the middle of the lane in slower traffic - Get in the middle of the lane at busy intersections and whenever you are moving at the same speed as traffic.•Choose the best way to turn left - There are two choices: (1) Like an automobile: Signal to move into the left turn lane and then turn left. (2) Like a pedestrian: Ride straight to the far side crosswalk. Walk your bike across.•Make eye contact with drivers - Assume that other drivers don't see you until you are sure that they do. Eye contact is important with any driver who might pose a threat to your safety.•Look out for road hazards - Watch out for parallel-slat sewer grates, gravel, ice, sand or debris. Cross railroad tracks at right angles.•Use lights at night - New York law requires a white headlight (visible from at least 500 feet ahead) and a red rear reflector or taillight (visible up to 300 feet from behind).•Keep your bike in good repair - Adjust your bike to fit you and keep it working properly. Check brakes and tires regularly. Routine maintenance is simple and you can learn to do it yourself.

Modern chemical plants use advanced and complex technology.

Chemical plants are the safest of all manufacturing facilities.

…….BUT …….

it has the potential for accident of CATASTROPIC proportions.

Chemical Process

Industry

Chemical Process Industry Disaster

Example of Major Disasters

• Flixborough, England 1974

Failure of temporary bypass pipe connecting reactor 4 toreactor 6 (this occurred while the reactor 5 was undergoingrepair)

Resulting in the release of 40 tons of liquid cyclohexane

Forming vapor clouds (100- 200 m diameter) that exploded,killing 28 people, injured 36. It was on Saturday, 1st June1974.

• Seveso, Italy 1976

Reactor out of control, produced excessive side product of

extremely toxic of dioxin (TCDD or agent orange) (2,3,7,8-

Tetrachlorodibenzodioxin) - the most toxic man-made

chemicals used for manufacture herbicides.

2 kg of vapor TCDD released to atmosphere through relief

system and heavy rain washed into soil.

250 people suffered from skin disorder (chloracne).

Bhopal, India 1984

Contaminated methyl isocynate (MIC) escaped when a valve in theplant's underground storage tank broke under pressure.

Vapor released through pressure relief system but the scrubber andflare systems failed to function. 25 tons of MIC vapor released.

Toxic cloud spread nearby town with 900,000 population,poisoning/killing 2500 civilian, injured more than 20,000. No plantworkers were injured or killed.

No plant equipment was damaged. The owner was Union Carbide(American based company).

Inlet

Scrubber

Flare

Flare

Gulf of Mexico oil spill, April 20, 2011

Explosion of the Deepwater Horizon rig - killed 11 workers and

unleashed an unprecedented ecological emergency in the Gulf.

More than 155 million gallons of crude seeped/leak out, causing

billions of dollars in cleanup costs and economic losses.

Poor safety practices, a faulty cement seal and a rush to meet a deadline

by BP and its subcontractors (Transocean and Halliburton) were key

causes of the explosion and oil spill.

Enhance safety and risk management throughout global operations of BP.

kickback of mud/gas

Nowadays……..

…….we have advanced safety technology/tools for the complex

chemical processes……..

So we need engineers with,

Sound technical knowledge (fundamental and application) of process

safety as well as experience in order to effectively apply the

technology.

“Safety” used to define as:

Strategy of accident prevention through the use of safety helmet, safety

shoes (PPE – Personal Protective Equipment) and a variety of rules

and regulation – the emphasis was on workers safety.

Nowadays, “safety” is used synonymously with “loss prevention”

- The prevention of accidents through the use of appropriate

technologies, to identify the hazards of a chemical plant and

eliminate them before an accident occurs (i.e. proactive)

Safety is also means freedom from unacceptable risk of harm.

[see ISO/IEC Guide : International Organization for Standardization

(ISO) and the International Electrotechnical Commission (IEC)]

Term Definition

Accident Undesired event giving rise to death, ill health, injury, damage or other

loss

Incident Event that gave rise to an accident or had potential to lead to an accident

(not all incidents propagate into accidents); as remainder for others!!

(An incident where no ill health, injury, damage, or other loss occurs is

referred to as ‘near-miss’)

Hazard Source or situation (chemical or physical) with a potential to cause harm,

injury or damage to either human, property or the environment or some

combination of these.

Mechanical hazards e.g. wet floor could cause tripping,

moving equipment that could cause collision etc.

Chemical hazards e.g. fuel leakage could cause fire, explosion,

toxic fumes form hazardous chemical etc.

Risk Combination of the likelihood (probability) of a specified hazardous event

occurring and its consequences

Risk

Assessment

Overall process of estimating the magnitude of risk and deciding whether

or not the risk is tolerable

• To ensure safe design, installation, commission, and operation

throughout the life of a plant.

• Need to identify all potential hazards or incident scenarios and to

minimize all risks using loss prevention techniques such as:

- inherent safety concept in design

- hazard identification methods

- technological advances using better design/control

- proper maintenance etc.

Notes

Any potential hazards need to be identified as early as possible so

that action can be taken to correct or mitigate/reduce the situation.

A successful safety program needs ingredients such as,

1. System e.g. OSHMS (Occupational Safety & Health Management

System), SHC (Safety Hire Scheme), SHO (Safety & Health Officer),

Policy, Regulation (Act) etc.

2. Attitude or awareness (example to do some of thankless work)

3. Fundamentals (technical knowledge to design, construct, operate,

maintain etc.)

4. Experience (learn from past accident, experience of others and

doomed to repeat it)

5. Time: safety takes time (to train, to set up system, to do hazard

identification, risk assessment, documentation and review etc.)

6. You….everyone should participate/contribute in all levels, safety is

equally important to production.

Safety Program

• Reduce disruption due to accidents,

• Reduce Workers-Company claims,

• Assist complying with regulatory/regulations requirements,

• Demonstrate due diligence/carefulness, shall your company ever need,

• Contribute to the morale and high level and esteem/respect,

• Assist promoting and maintaining organisation image,

• Expedite/speed-up the safe, successful induction/training of personnel,

• Assist in the induction of new personnel or cross functional training, and

• Add requirements to contractors thus reducing hazards—risks

• Demonstrate conformance (obey the rules) to others such as

stakeholders…

• Demonstrate social responsibility.

OSHMS(Occupational Safety & Health Management System) provides a

framework/support to:

(An example of comprehensive system for the safety management)

AIChE’s Code of Professional Ethics

Fundamental principles

• Engineers shall uphold and advance the integrity, honor and

dignity of engineering profession by :

1- using knowledge & skill for enhancement of human welfare.

2- honest, impartial/fair and serving with fidelity/reliability to

public, employers, clients.

3- striving to increase competence/fitness and prestige of

engineering profession.

AIChE’s Code of Professional Ethics

Fundamental canons/rules (for engineers)

• Shall hold paramount/top safety, health and welfare of public in

performance of their professional duties.

• Shall perform services only in areas of their competence/fitness.

• Shall issue public statements only in an objective and truthful

manner.

• Shall act in professional matters for each employer or client as

faithful agents or trustees, shall avoid conflicts of interest.

• Shall build their professional reputations on merits of their services.

• Shall act in such manner as to uphold/support and enhance the

honor, integrity and dignity of engineering profession.

• Shall continue their professional development throughout their

careers and shall provide opportunities for professional

development of those engineers under their supervision.

A Concept Question

Two dams are identical in size and shape and the water levels at both

are the same. One dam holds back a lake containing 2 million m3 of

water while the other hold back a 4 million m3 lake. Which statement is

correct concerning the average force on the dams?

Give your answer either :

The dam with the larger lake has twice the average force on it.

The dam with the smaller lake has twice the average force on it.

The dam with the larger lake has a slightly larger average force on it or

None of the above.

• Accident and loss statistics caused to measure the

effectiveness of safety programs.

• Among statistical methods used to re characterize

accident and loss performance :

1. OSHA Incidence Rate (OSHA IR)

2. Fatal Accident Rate (FAR)

3. Fatality rate or deaths per person per year

• These methods report number of accidents and/or

fatalities for fixed number of workers during specified

period.

Here OSHA refers to,

Occupational Safety and Health Administration, USA

….i.e. similar to DOSH (Department of Occupational Safety and

Health) in Malaysia

Some glossary/dictionary of terms used by OSHA (USA)

• Occupational injury- Any injury such as cut, fracture, sprain/twist,

amputation/elimination etc. as a result from work accident or from exposure

involving single incident in the work environment.

• Occupational illness- Any abnormal condition, caused by exposure to

environment factors associated with employment. It includes acute and

chronic illnesses or diseases that may be caused by inhalation, absorption,

ingestion, or direct contact.

• Lost workdays- Days which employee normally work but could not because

of occupational injury or illness. This day does not include/exclusive the day

of injury.

Note: Table 1-2 (page 6) is given more definitions (Text Book).

• Occupational safety – the protection of people/workers from physical injury.

• Occupational health – the protection of the bodies and minds of

people/workers from illness

More definitions…

1. OSHA Incidence Rate (OSHA IR)

• Based on cases per 100 worker in 1 year.

• Two types of calculation

OSHA IR(1) : Based on injuries and illness (including fatalities)

OSHA IR(2) : Based on lost workdays

1 worker year = 50 work weeks

yr

40 hrs

week 2000 hrs

100 worker years = 100x2000 = 200,000 hrs worker exposure to hazard

OSHA IR(1) = Number of injuries/illness/fatalities x 200000

Total hrs work by all employees during period covered

OSHA IR(2) = Number of lost workdays x 200000

Total hrs work by all employees during period covered

OSHA Incidence Rate (OSHA IR)

Examples:

1) A company with 100 workers recorded 10 injuries in one year.

OSHA IR(1)=10x200000

100x2000 10

We could say, OSHA IR as a number of injury per 200,000 working

hours or exposed hours

Examples:

2) A company with 50 workers recorded 10 injuries in one year.

3) A company with 10 workers recorded 10 injuries in one year.

4) A company with 50 workers recorded 10 injuries in 6 months.

OSHA IR(1)=10x200000

50x2000 20

OSHA IR(1)=10x200000

10x2000 100

OSHA IR(1)=10x200000

50x1000 40

Number of hrs per worker in half-year

2. Fatal Accident Rates (FAR)

• FAR is used by British chemical industries. FAR data is widely available

in open literature.

• Based on 1000 employees working for 50 years during their lifetime.

so, 1000 x 50 x 2000 = 108 working hrs or exposed hrs

We could say, FAR as number of deaths per 108 working hrs or

exposed hrs.

FAR = Number of fatalities x 108

Total working hrs by all employees during period covered

Number of hrs per worker in a year

Example: FAR

In Table1-3, FAR for construction industry is 5 for year 1990,

This means that if 1000 workers begin employment in the

industry, 5 of the workers will die as a result of their

employment throughout all of their working lifetimes (i.e. 50

years).

Check:

or

We could say that for every 50000 workers in the construction

industry in year 1990, 5 of them died in work related accident.

FAR=5x108

1000x50x2000

5x108

108 5

Number of workers in 50 years

More rock climbers are killed than traveling by car. Is this statement supported by statistics?

From data (Table 1-4), Traveling by car, FAR=57,

Rock climbing, FAR = 4000.

(Table 1-3) Occupational accident, FAR = 1.2

Answer: Yes or No….?

Statistics say rock climbing produces more fatalities per exposed hrs.

We need more data (i.e. exposed hrs) to actually calculate the number of fatalities.

Example: FAR

Example: FAR

A rock climbing club has 1000 members working in chemical industry,on average each member spend 3 hrs/day driving and 2 hrs/monthclimbing. In 10 years how many member will die due to rock climbing,road accident and occupational accident.

FAR=Number of fatalities x 108

Total working hrs by all employees during period covered

in this case,

FAR=Number of fatalities x 108

Total exposed hrs by all members during 10 year period

Answer: to compute the Number of Fatalities

ROCK CLIMBING

Number of fatalities =FAR

108x(Total hrs climbing by all member in 10 years)

Number of fatalities =4000

108x(1000x2x12x10) = 9.6 deaths

ROAD ACCIDENT

Number of fatalities =FAR

108x(Total hrs on the road by all member in 10 years)

Number of fatalities =57

108x(1000x3x365x10) = 6.2 deaths

ACCUPATIONAL ACCIDENT

Number of fatalities =FAR

108x(Total hrs working by all member in 10 years)

Number of fatalities =1.2

108x(1000x2000x10) = 0.24 deaths

OCCUPATIONAL ACCIDENT

Number of hrs per worker in a year

The OSHA Incidence Rate (OSHA IR) and FAR accident statistics,

in Table 1-3, showed a decrease for all selected industries

for 1990 as compare to 1986.

Discuss why?

Although statistically shows that chemical industry is safe, why there

is more concern about chemical plant safety?

The concern regarding the industry’s potential for many deaths,

i.e Bhopal tragedy

Actually, accident statistics do not include information on the

total number of deaths from a single incident.

Thus, the accident statistics can be somewhat misleading in this respect.

For example:

Chemical Plant A : employs 1 operator, explosion happened only 1 fatality.

Chemical Plant B : employs 10 operator, explosion happened 10 fatality.

In both cases the OSHA IR and FAR are the same.

Chemical Plant B explosion killed more people, but corresponding to

large number of exposed hours.

For both Chemical Plants, the risk taken by an individual operator is the same.

Thus, we need to compute the Fatality Rate:

3. FATALITY RATE

or

Fatality Rate = (Exposed hrs per person per year) x FAR

Unit for Fatality Rate is deaths/person.year

Fatality rate can be calculated/used if the number of working hrs or

exposed hours is poorly defined/not known.

FAR can be converted to Fatality Rate (or vice versa) if number of exposed

hours is known.

Fatality Rate = Number of fatalities per year

Total number of people in applicable population

Example 1-1

A process has a reported FAR of 2. If an employee works 8 hr shift 300

days per year, compute the deaths per person per year (or Fatality Rate).

OSHA incidence rate (OSHA IR) cannot be converted to FAR or Fatality

Rate because it contains both injury & fatality information.

Fatality Rate = Exposed hrs/person/year x(FAR)

Fatality Rate = 8hr

day.person

300day

yr

2deaths

108hr 4.8x105 deaths

person.year

FAR

108 : working hrs or exposed hrs from FAR

Example: Fatality Rate

An industry has a reported FAR of 57. If an employee works 8 hr shift 300

days per year, compute the deaths per person per year (or Fatality Rate).

Fatality Rate = (Exposed hrs per person per year) x FAR

= (8hr/day)(300day/yr) 57deaths/108hr

= 1.368x10-3 deaths/person.year

A Concept Question

The Wood and Iron have equal volumes. The wood floats while the iron

sinks in water. Which has the greater buoyant force on it?

Give your answer, either:

The Wood.

The Iron or

They have equal buoyant forces on them.

ᵖ = density of fluid

V = submerged volume of an object

g = gravitational acceleration (9.81m/s2)

Answer:

Risk Acceptance and ALARP

(As low As Reasonably

Practicable) Concept

• Risk cannot be eliminated entirely.

• Every chemical process has a certain amount of risk.

• At some point in the design stage someone needs to decide if

the risks are “tolerable".

• One tolerability criteria in the UK is “As Low As Reasonably

Practicable" (ALARP) concept; formalized in 1974 by United

Kingdom Health and Safety at Work Act.

• Tolerable risk is defined as the risk that has been reduced to a

level that can be tolerated/endured/bared by the organization

having regards to its legal obligations and its own OHS policy.

1 Death/Disabling injury

100 Minor Injury

500 Property Damage

10000 No Damage (near misses)

The Accident PyramidNo damage is refers to near misses incident – give opportunity for a industry –

investigate the problem occurs – correct – before a more serious incident

happens

Property damage is much more common than fatality as shown in Figure of

Accident Pyramid (Fig.1-3).

Lost prevention is includes: property damage + production lost.

Approximate

number of accident Fig.1-3

• Individual risk (IR) is the frequency at which an individual

may be expected to sustain a given level of harm from

specified hazard.

It has been suggested that IR ~ 2.2 x 10-5 x FAR.

• Occupational risk is a risk that may happen at the work

place. Usually given in term of FAR.

• Societal/Shared risk is a frequencies of risk which

specified numbers of people in a given population sustain

a specified level of harm from specified hazards.

This framework is represented as a three-tier system as

shown in figure (next slide) “ALARP criteria”.

It consists of several elements :

Intolerable level: Beyond the upper-bound on individual

(and possibly, societal risk) risk levels.

Tolerable (ALARP) region between (1) and (3) i.e in region

(2), risk is undertaken only if benefit is desired after

considering the cost on individual and societal risk reductions.

Negligible risk (acceptable region): below the lower-bound on

individual (and possibly, societal risk) risk levels.

This level is not to issues warrant/permit regulatory.

INTOLERABLE

LEVEL

(Risk cannot be

justified on any

ground)

THE ALARP

REGION

(Risk is undertaken

only if benefit is desired)

BROADLY

ACCEPTABLE

REGION

(No need for

detailed working

to demonstrate

ALARP)

TOLERABLE only if risk

reduction is impraticable

or if its cost is grossly

disproportionate to the

improvement gained

TOLERABLE if cost of

reduction would exceed

the improvement gained

NEGLIGIBLE RISK

Incre

asin

g i

n in

div

idu

al ri

sks a

nd

so

ceit

al

co

ncern

s

Region 1

Region 2

Region 3

Incre

asin

g i

n in

div

idu

al ri

sks a

nd

so

ceit

al

co

ncern

s Intolerable region:

risk cannot be

justified on any

ground

Further risk reduction is

impracticable or if its

cost is clearly unequal /

disproportionate to the

improvement gained

Risk undertaken

only if a benefit is

desired

Tolerable if cost of risk

reduction exceed the

improvement gained

Broadly acceptable region of negligible

risk: no need for detailed work to

demonstrate ALARP

• From one public survey, 28% say chemicals do more

good than harm, 29% say more harm than good, 38% say

same amount of good and harm.

• Some naturalists/natural scientists suggest eliminating

chemical plant hazards by “returning to nature”

e.g. to eliminate synthetic fibers production and use

natural fibers such as cotton….. However, FAR for

agriculture is actually higher than chemical industry.

See Table 1-3 (page 8 in Text Book)

57

Accidents have direct, indirect and root causes:

Direct cause – attribute to equipment failure or unsafe

operating conditions

Indirect cause – not as readily apparent/obvious and

can generally be tied to some human failure

Root cause – result of poor management safety

policies, procedures or decisions

Note:

This causes do not include natural hazards such as

flood and windstorm etc.

58

Type of

accident

Probability of

occurrence

Potential for

fatalities

Potential for

economic loss

Fire High Low Intermediate

Explosion Intermediate Intermediate High

Toxic release Low High Low (equipment)

Other such as

clean-up, legal etc.

can be high

Table 1-6 : Three Type of Chemical Plant Accidents Patterns

0

5

10

15

20

25

30

35

40

45

Mechanical 44

Operator error 22

Unknown 12

Process upsets 11

Natural hazards 5

Design 5

Sabotage & Arson 1

Note: Except for natural hazards, all of these causes can be traced back to human error.

Figure 1-7: Causes of Losses (accidents) associated with 100 of the largest property

damage losses in hydrocarbon-chemical industry: A 30 year review

A

c

c

i

d

e

n

t

s

%

Figure 1-8 Hardware associated with 100 of the largest property damage

losses in hydrocarbon-chemical industry: A 30 year review

0

5

10

15

20

25

30

Piping system 30

Unknown 23

Storage tank 19

Reactor piping 11

Process holding tank 6

HEXs 4

Valves 4

Process Towers 3

Compressors 2

pumps 2

Gauges 2

Number

of

Accidents

Figure 1-9 Loss distribution for onshore accidents for 5-year intervals over 30-year period

0

0.5

1

1.5

2

2.5

3

1967-71(5 losses)

1972-76 (9 losses)

1977-81 (17 losses)

1982-86 (16 losses)

1987-91 (27 losses)

1992-96 (18 losses)

Total

Loss

(billion

US$)

Note: OSHA legislation on Process Safety Management of Highly

Hazardous Chemicals was introduced (in USA) in the year 1992

CONCLUSIONS

• Safety comes first !!!

• Two Important Elements

– Human Factor

We Need Good Safety Management Practice

– Safe Design

Need to Incorporate Inherently Safe Design

• Next class will look at both issues.