Risk IdentificationRisk Identification

Hazards and RiskHazards and Risk

Section 2: ACCIDENT THEORIESSection 2: ACCIDENT THEORIES

2.1 Single Factor Theories2.1 Single Factor Theories This theory stems from the assumption that an accident is This theory stems from the assumption that an accident is

the result of a single cause. Further, if that single cause can the result of a single cause. Further, if that single cause can be identified and eliminated the accident will not be be identified and eliminated the accident will not be repeated. repeated.

This theory is generally not accepted by persons who have This theory is generally not accepted by persons who have even the most basic safety and health training.even the most basic safety and health training.

Example: A person in a hurry walks through a poorly lit area Example: A person in a hurry walks through a poorly lit area and trips over a piece of wood.and trips over a piece of wood.

Single Factor Theory Solution: Single Factor Theory Solution: Remove the offending piece of wood to solve the problem.Remove the offending piece of wood to solve the problem. The reality is that accidents always have more than one The reality is that accidents always have more than one

contributing factor.contributing factor.

2.2 Energy Theory2.2 Energy Theory

The energy theory proposed by William Haddon The energy theory proposed by William Haddon states that accidents are more likely to happen at states that accidents are more likely to happen at or during a transfer of energy. or during a transfer of energy.

The rate of energy release is important because The rate of energy release is important because the greater the rate of release the greater the the greater the rate of release the greater the potential for damage.potential for damage.

The energy theory is discussed in more detail in a The energy theory is discussed in more detail in a subsequent reading. It should be noted that this subsequent reading. It should be noted that this concept of identifying hazards is very limited and concept of identifying hazards is very limited and not dissimilar to the Single Factor theory.not dissimilar to the Single Factor theory.

Factors other than energy release are important.Factors other than energy release are important.

2.3 Multiple Factor Theory2.3 Multiple Factor Theory

The multiple factor theory, says that an The multiple factor theory, says that an accident occurs when number of factors accident occurs when number of factors act together to cause an accident. act together to cause an accident.

This and similar ideas are favoured by This and similar ideas are favoured by most experienced safety and healthmost experienced safety and healthpractitioners.practitioners.

Example: A person in a hurry walks Example: A person in a hurry walks through a poorly lit area and trips over a through a poorly lit area and trips over a piece of wood.piece of wood.

Multiple Factor Theory Solution:Multiple Factor Theory Solution:

to effect a solution the multiple factor theory to effect a solution the multiple factor theory would require answers to such questions would require answers to such questions as:as:

was there a necessity for that person to was there a necessity for that person to walk in that area or was there a safer walk in that area or was there a safer route;route;

if the person was not in a hurry would they if the person was not in a hurry would they have been more aware of their have been more aware of their surroundings and avoided the wood;surroundings and avoided the wood;

if the area was better lit would the person if the area was better lit would the person have avoided the wood; andhave avoided the wood; and

could the wood have been removed.could the wood have been removed.

2.4 Domino Effect2.4 Domino Effect

This theory is attributed to W F This theory is attributed to W F Heinrich and postulates that the Heinrich and postulates that the events, which lead to an injury, are events, which lead to an injury, are like five dominos, standing on end, like five dominos, standing on end, ready to knock each other over in ready to knock each other over in turn.turn.

The DominoThe Domino

The Domino are:The Domino are: Social Environment:Social Environment:

– Those conditions which make us take or accept risks.Those conditions which make us take or accept risks. Undesirable Human Traits:Undesirable Human Traits:

– Anger, carelessness, tiredness, lack of understanding, Anger, carelessness, tiredness, lack of understanding, inattention.inattention.

Unsafe Acts or Conditions:Unsafe Acts or Conditions:– Poor planning, unsafe equipment, hazardous Poor planning, unsafe equipment, hazardous

environment.environment. The Accident: The Accident:

– The accident occurs when the above events conspire to The accident occurs when the above events conspire to cause something to go wrong.cause something to go wrong.

The Injury: The Injury: – Injury occurs when the person sustains damage.Injury occurs when the person sustains damage.

Combining the elements of the Combining the elements of the TheoriesTheories

Often accidents occur without injury and Often accidents occur without injury and they are referred to as near misses. they are referred to as near misses.

All too often, these near misses are All too often, these near misses are ignored until, figuratively speaking, the ignored until, figuratively speaking, the last domino is knocked over and the injury last domino is knocked over and the injury occurs.occurs.

The domino theory has its merits but may The domino theory has its merits but may be too limited to consistently reflect be too limited to consistently reflect reality. reality.

A more accurate picture of reality may be A more accurate picture of reality may be gained by combining the elements of the gained by combining the elements of the Multiple Factor Theory and the Domino Multiple Factor Theory and the Domino Effect.Effect.

Identifying Risk in Identifying Risk in EmploymentEmployment

(OHS)(OHS)

Two approaches to risk IDTwo approaches to risk ID

Theoretical ApproachTheoretical Approach– Prepare or obtain a Standard operating Prepare or obtain a Standard operating

procedure (SOP)procedure (SOP)– Prepare a list of task indicated in SOPPrepare a list of task indicated in SOP– Assess the possible risk involved in each Assess the possible risk involved in each

tasktask– Recommend and if need be implement Recommend and if need be implement

risk mitigation proceduresrisk mitigation procedures– Brainstorming with a group of people to Brainstorming with a group of people to

think of possible hazardsthink of possible hazards

Second ApproachSecond Approach Empirical approachEmpirical approach

– Physical inspection of thePhysical inspection of theworkplaceworkplaceRequires a check listRequires a check list

– Examination of Examination of Previous Accident Previous Accident Reports may not show hazards if Reports may not show hazards if accidents have not happend yet.accidents have not happend yet.

– Lack accidents may due to skill of Lack accidents may due to skill of workers ( 1workers ( 1stst approach may be needed approach may be needed as well)as well)

Previous Accident ReportsPrevious Accident Reports

Review the history of the area: any Review the history of the area: any accidents or near misses should be accidents or near misses should be carefully investigated. carefully investigated.

Sources for this information wouldSources for this information would include workers compensation records and include workers compensation records and

company accident records. company accident records. At this stage it is worth sorting all the past At this stage it is worth sorting all the past

accidents and near miss information into a accidents and near miss information into a number of categories.number of categories.

Typically these category of Typically these category of AccidentsAccidents

LocationLocation MachineMachine PersonPerson Age of PersonAge of Person Time of DayTime of Day

Day of WeekDay of Week Part of BodyPart of Body Severity of InjurySeverity of Injury OccupationOccupation

TrendsTrends

Identifying a trend of accidents in any of the Identifying a trend of accidents in any of the above areas may assist the investigator above areas may assist the investigator identify a possible hazard. identify a possible hazard.

Sometimes the results of sorting accident Sometimes the results of sorting accident information is surprising because the information is surprising because the accidents and near misses may be centered accidents and near misses may be centered around a particular person or confined to a around a particular person or confined to a particular time of the day or week. particular time of the day or week.

This knowledge will assist the investigator This knowledge will assist the investigator during the risk assessment and control during the risk assessment and control phases of the risk management processphases of the risk management process

Physical inspection of thePhysical inspection of theworkplaceworkplace

A physical examination of the workplace A physical examination of the workplace requires an inquiring mind, lateral requires an inquiring mind, lateral thinking, and the ability to be and remain thinking, and the ability to be and remain open minded. open minded.

It is of little use to look at a particular area It is of little use to look at a particular area and, in a perfunctory manner, declare it to and, in a perfunctory manner, declare it to be hazard free.be hazard free.

Some of the tools used to make sure all Some of the tools used to make sure all avenues of inquiry have been explored avenues of inquiry have been explored follow.follow.

BrainstormingBrainstorming

This is a process of conducting group This is a process of conducting group meetings with people who are meetings with people who are familiar with the operation of the familiar with the operation of the area under review,area under review,

Recording all ideas and thoughts Recording all ideas and thoughts relating to possible hazards and relating to possible hazards and

then sorting the results into some then sorting the results into some sort of priority order.sort of priority order.

Knowledge of EmployeesKnowledge of Employees

Employees should be encouraged to Employees should be encouraged to describe any hazards they are aware of.describe any hazards they are aware of.

Inquiries of this nature should be Inquiries of this nature should be conducted in an atmosphere of 'no blame' conducted in an atmosphere of 'no blame' where even if the employee is not doing where even if the employee is not doing things properly they are not criticised for things properly they are not criticised for it. it.

The aim is to identify and document The aim is to identify and document hazards at this stage.hazards at this stage.

Trade JournalsTrade Journals

Trade journals are often a source of Trade journals are often a source of information regarding hazards information regarding hazards encountered by others in the encountered by others in the industry. industry.

They can be a source of useful They can be a source of useful inquiry, as members of the same inquiry, as members of the same industry would expect to encounter industry would expect to encounter similar hazards.similar hazards.

OtherOther

OSH PublicationsOSH Publications These publications can be of particular These publications can be of particular

benefit as they concentrate on reporting benefit as they concentrate on reporting issues relating to safety and health.issues relating to safety and health.

ContactsContacts A counter-part in another subsidiary of the A counter-part in another subsidiary of the

company or even a contact in a company or even a contact in a competitive company could be a good competitive company could be a good source of information as they probably source of information as they probably share similar safety problems.share similar safety problems.

Industry AssociationsIndustry Associations

Safety and health is often brought up Safety and health is often brought up at industry association meetings or at industry association meetings or during informal discussions before or during informal discussions before or after meetings.after meetings.

An investigator could gain useful An investigator could gain useful information by promoting safety and information by promoting safety and health discussion at such meetings.health discussion at such meetings.

Manufacturers’ Instruction Manufacturers’ Instruction BooksBooks

Manufacturers instruction books often Manufacturers instruction books often provide advice and warnings regarding provide advice and warnings regarding safety and health issues. safety and health issues.

It is important to ensure all instructions It is important to ensure all instructions are understood and, more importantly, are understood and, more importantly, followed by all employees.followed by all employees.

Manufacturers' information, including Manufacturers' information, including material safety data sheets, should always material safety data sheets, should always be reviewed to ensure the products in use be reviewed to ensure the products in use are the safest available and do not have are the safest available and do not have hidden hazards.hidden hazards.

"What if?....""What if?...."

Ask, “What If…?”Ask, “What If…?” Its important to try to anticipate how Its important to try to anticipate how

human behavior, plant, and system human behavior, plant, and system failures could combine to create a failures could combine to create a hazardous situation.hazardous situation.

Constantly ask yourself "What if?...."Constantly ask yourself "What if?...."