Theories of Accident Causation

CII OSHA Recordable Performance - 1993-2000

Lost Time 1 Recordables 10.4 297 First Aid Near Misses??

A DISPROPORTIONATE NUMBER OF ACCIDENTS OCCUR IN CONSTRUCTION Nearly 6.6% of the industrial workforce is in construction. But, over 18% of the fatalities occur in construction (~1,200 fatalities per year) And, over 12% of the disabling injuries occur in construction (over 500,000 injuries per year) Do these statistics have anything to do with firms serious about safety?

What Is An Accident? Unplanned event Generally associated with negative consequences Fatalities Injuries Near misses Damaged materials Shattered nerves Do accidents just happen or are they caused?

Theories of Accident Causation Understanding the causes of accidents may lead to an effective means of their prevention. No worker wants to be injured, but it still happens thousands of times every working day. Why??

1: Accident Proneness Theory

Accident-Proneness Theory Old View “Injuries happen to people who have a genetic predisposition to being injured” The theory states that there are inherent characteristics of some individuals that predispose them to a greater probability of being involved in accidents.

Accident-Proneness Theory A very controversial theory Many research studies have been conducted which lend support for the theory (Studies show injuries are not randomly distributed, but do studies recognize differences in hazard exposure?) Other studies have shown that there is no basis for the theory

Accident-Proneness Theory New View Recent researchers view accident proneness as being associated with the propensity of individuals to take risks or to take chances. This presents a more positive view for safety, as behavior can be altered even if the propensity to take risks cannot.

2: GOALS-FREEDOM-ALERTNESS THEORY

Goals-Freedom-Alertness Theory This is a fundamental concept that accidents are the result of low quality (unsafe) behavior resulting from an unrewarding psychological climate that does not contribute to mental alertness.

Goals-Freedom-Alertness Theory Workers should have the ability to set attainable goals. Workers should have the freedom to pursue their goals. This will result in a “rich” work climate with alertness and fewer accidents (Workers stay focused)

Goals-Freedom-Alertness Theory A positive work environment is good for safety.

3: ADJUSTMENT STRESS THEORY

Adjustment Stress Theory A negative work environment contributes to accident causation. A negative work environment is often caused by stress. Excessive stress prevents the individual from focusing on the work.

Adjustment Stress Theory Stress comes from many sources. On the Job Poor relationship with the supervisor Poor relationship with crew members Harsh deadlines Poor coordination Excessive rework Cost overruns Long overtime commitments Crowded work areas Jobsite hazards

Adjustment Stress Theory Stress comes from many Sources. Off the Job Poor relationship with the spouse  sick child  mortgage due date

4: Chain of Events

Chain of Events This is not truly a theory of accident causation, but is often referred to as one. It is really a conceptual portrayal of how accidents occur. The chain of events states that there is not a single cause of an accident but there are many causes an accident.

Chain of Events In general, every accident is preceded by a series of events or activities. If any one event or activity had been done differently, the accident would not have occurred (“break the chain to avoid the accident”). Different people may be associated with the different links in the chain.

Chain of Events This has implications for many parties on the construction site (the worker who was injured, the worker’s crew, the foreman, the superintendent, other crews, the project manager, the subcontractors, the safety rep., etc.). There are many links in the chain and only one link needs to be broken. Also called the Domino Theory

Contributing Factors If I had done this, that would not have happened Only one party is required to break the chain!!

5: Distraction’s Theory

Distraction’s Theory This theory states that accidents are caused when workers are distracted when they are performing their work tasks. There are two types of distractions.

Distraction’s Theory or Jobsite Hazards can be a source of distraction Workers will try to avoid being injured so they naturally focus on the hazard, but this occurs as they are trying to do work. Trying to get the task done may cause the worker to be distracted and to ignore the hazard, resulting in an injury. Focus on the Hazards The Dilemma: or Focus on Getting Tasks Done

Safe Zone Safe Zone Probability of Injury Occurrence low Distraction: high low focus on distraction Distraction: Working near a powerline Probability of Injury Occurrence high focus on distraction Safe Zone Safe Zone low low high Work Task Achievement

Probability of Injury Occurrence high Probability of Injury Occurrence Distraction: Minor Hazard low focus on distraction high focus on distraction low low high Work Task Achievement

Low Focus on Hazard High Focus on Hazard Low High Task Achievement Injury Occurrence Low Focus on Hazard High Focus on Hazard Low High Task Achievement

Don’t work in this zone!!! Low Focus on Hazard High Focus on Hazard Injury Occurrence Don’t work in this zone!!! Low Focus on Hazard High Focus on Hazard Low High Task Achievement

Distraction’s Theory Mental worries can be a source of distraction. Workers will try to focus on the work to be done, but may be distracted by worries caused by personal or job-related concerns. Failure to be able to focus on the work increases the likelihood of being injured. Remember the Holmes and Rahe Scale

Can distracted workers be identified? high high focus on distraction Major Mental Distraction Probability of Injury Occurrence low focus on distraction low low high Work Task Achievement Can distracted workers be identified?

Each of the Accident Theories Help Our Understanding of Accident Causation Remember, no worker wants to be injured. Worker tasks should be structured so they are least likely to be injured.

How to Achieve Safety: Don’t permit unsafe behavior Provide a rewarding work environment Make everyone responsible for safety Provide a safe work environment

Thank you!!!