Industrial SafetyLecture 2

Theories of Accident Causation

Contents

• Accident Causation

• The Job of the Safety Manager

• Typical College Majors

• A modern safety and health team

• Professional Certification

• Productivity: A Global View

Accident Causation (1 of 3)

• Each year, work-related accidents cost almost $50 billion in lost wages, medical expenses, insurance costs, and indirect costs.

• The number injured in industrial place accidents in a typical year is 7,128,000.

– 3 per 100 persons per year

Accident Causation (2 of 3)

• There is an accidental workplace death about every 51 minutes, and one injury every 19 seconds.

• Why do accidents happen?

– To prevent accidents we must know why they happen.

Accident Causation (3 of 3)

• The most widely known theories of accident causation are:

1. The domino theory

2. The human factors theory

3. The accident/incident theory

4. The epidemiological theory

5. The systems theory

6. The combination theory

7. The behavioral theory

1. The Domino Theory of Accident Causation(1 of 2)

• The domino theory of accident causation

– One of the earliest developed

– Posits that injuries result from a series of factors, one of which is an accident

– Operationalized in 10 statements called the Axioms of Industrial Safety

1. The Domino Theory of Accident Causation(2 of 2)

• According to this theory, there are five factors in the sequence of events leading to an accident:

– Ancestry and social environment

– Fault of person

– Unsafe act/mechanical or physical hazard

– Accident

– Injury

Factors that cause human errors.

Inappropriate Response and Incompatibility

• Inappropriate responses in a given situation can lead to accidents.

– Detecting a hazardous condition and not to correcting it

– Removes a machine safeguard from to increase output

– Disregarding an established safety procedure

• Workstation incompatibility

– Incompatibility of a person’s workstation with regard to size, force, reach, feel, and similar factors can lead to accidents and injuries.

Overload

• Overload—imbalance between a person’s capacity at any given time and the load that person is carrying in a given state.

– Capacity is a product of natural ability, training, state of mind, fatigue, stress, and physical condition.

– Load consists of tasks for which a person is responsible, and

• Added environmental burdens (noise, distractions, etc.)

• Situational factors (level of risk, unclear instructions, etc.)

Inappropriate Activities

• Human error can be the result of inappropriate activities

– When a person undertakes a task that he/she doesn’t know how to do

• Such inappropriate activities can lead to accidents/injuries.

Safety Fact Pregnancy and Work

2. Human factors theory.

3. Accident/Incident Theory of Causation(1 of 4)

• An extension of the human factors theory was developed by Dan Petersen, introducing:

– Ergonomic traps

– Decision to err (stray)

– Systems failures

3. Accident/Incident Theory of Causation(2 of 4)

3. Accident/Incident Theory of Causation(2 of 4)

• Following are just some of the different ways that systems can fail, according to Petersen’s theory:

– Management does not establish a comprehensive safety policy.

– Responsibility and authority with regard to safety are not clearly defined.

3. Accident/Incident Theory of Causation(3 of 4)

– Safety procedures are ignored or given insufficient attention.

• Such as measurement, inspection, correction, and investigation

– Employees do not receive proper orientation.

– Employees are not given sufficient safety training.

3. Accident/Incident Theory of Causation(4 of 4)

• Decision to err may be conscious, based on logic, or it may be unconscious.

– Overload, ergonomic traps, deadlines, budget factors, and peer pressure can lead to unsafe behavior.

– The “It won’t happen to me” syndrome.

4. Epidemiological Theory of Causation (1 of 2)

• Current safety theories/programs trend to a broad perspective encompassing industrial hygiene.

– Concerns environmental factors that can lead to sickness, disease, or other forms of impaired health

4. Epidemiological Theory of Causation (2 of 2)

• Epidemiology is the study of causal relationships between environmental factors and disease.

– The epidemiological theoryuses those models to study relationships between environmental factors and accidents or diseases.

4. Epidemiological theory.

5. Systems Theory of Accident Causation

• A system is a group of regularly interacting and interrelated components that form a unified whole.

• The systems theory of accident causation views a situation in which an accident may occur as a system comprised of the following components:– Person (host)– Machine (agency)– Environment

5. Systems theory model.

Likelihood of an accident occurring is determined by how these components interact.

- Changes in the patterns of interaction can increase or reduce the probability of an accident.

6. Systems Theory of Accident Causation

• As a person interacts with a machine within an environment, three activities take place:

– Collects information by observing and noting current circumstances

– Weighs risks

– Decides whether to perform the task

• If information was right and the risk assessment accurate, the task will probably be accomplished without accident.

6. Systems Theory of Accident Causation

• Five factors should be considered before beginning the process of collecting information, weighing risks, and making a decision:

– Job requirements

– Workers’ abilities and limitations

– The gain if the task is successfully accomplished

– The loss if the task is attempted but fails

– The loss if the task is not attempted

Combination Theory of Causation

• Often, the cause of an accident cannot be adequately explained by one model or theory.

– According to the combination theory, the actual cause may combine parts of several different models.

– Safety personnel should avoid the tendency to try to apply one model to all accidents.

Behavioral Theory of Causation

• This theory of accident causation and prevention is often referred to as behavior-based safety (BBS).

• It has seven basic principles:

1. Intervention that is focused on employee behavior

2. Identification of external factors that will help understand and improve employee behavior

3. Direct behavior with activators or events antecedent to the desired behavior, and motivation of the employee to behave as desired with incentives and rewards

4. Focus on the positive consequences that will result from the desired behavior as a way to motivate employees

5. Application of the scientific method to improve attempts at behavioral interventions

6. Use of theory to integrate information rather than to limit possibilities

7. Planned interventions with the feelings and attitudes of the individual employee in mind

The Job of the Safety Manager

• The job of the safety and health manager is complex and diverse, focusing on:

– Analysis

– Prevention

– Planning

– Evaluation

– Promotion

– Compliance

Typical College Majors

• Educational requirements range from technical certificates to graduate degrees.

• Typical college majors held by practitioners include:– Industrial safety and health technology– Industrial technology– Industrial engineering technology– Manufacturing technology– Industrial management– Engineering technology

Responsibilities of Industrial Hygienists

• Industrial hygienists are concerned with:– Recognizing the impact of

environmental factors on people– Evaluating the potential hazards

of environmental stressors– Prescribing methods to

eliminate stressors

Occupational Physicians Defined

• Occupational physicians are medical doctors who specialize in workplace-related health problems and injuries.

• In the past, occupational physicians treated injuries and illnesses as they occurred.

• Today’s occupational physicians focus more attention on anticipating and preventing problems.

Occupational Health Nurses Defined

• Occupational health nurses are concerned with conserving the health of workers through:– Prevention– Recognition– Treatment

• Like occupational physicians, occupational health nurses focus more attention on anticipation and prevention than they did in the past.

Risk Management Defined

• Risk management

involves the application of

risk reduction strategies

and transferring remaining

risk to insurance

companies.

A modern safety and health team.

Professional Certification

• Professional certification is an excellent way to establish credentials in the safety, health, and environmental profession.

• The most widely pursued certifications are:– Certified Safety Professional– Certified Industrial Hygienist– Certified Professional Ergonomist– Certified Occupational Health Nurse

Other Related Certifications

• Graduate Safety Professional (GSP)

• Associate Safety Professional (ASP)

• Occupational Health and Safety Technician (OHST)

• Construction Health and Safety Technician (CHST)

• Safety Trained Supervisor (STS)

• Certified Environmental, Safety, and Health Trainer (CET)

Productivity: A Global View

• Pressure to increase productivity often results in actions detrimental to the worker safety and health.

• In a rush to meet deadlines or quotas, workers may take chances they wouldn’t under normal conditions.

– Such efforts occasionally result in short-term productivity improvements, but invariably do more harm than good.

• Safety and health professionals will probably face similar situations.

Key areas that result in competitiveness.

• Safety, Health, and Competition in the Global Marketplace

Increases in output per hour of workers (Since 1950).

OSHA and Competitiveness

• Because OSHA regulations help ensure a safe and healthy workplace, they can be shown to improve productivity by educing the unproductive costs of accidents and injuries.

Discussion Case - individual What Is Your Opinion?

Team Assignments

• Heinrich’s 10 Axioms of Industrial Safety

• What are the most widely known theories of accident causation- theory in practice?

• Show understanding and awareness of all Accident Causation Models i.e. Swiss Cheese Model?