Herbert William Heinrich, author of Industrial Accident Prevention, A Scientific Approach, devised a way of understanding the relationship between unsafe acts and workplace injuries. He illustrated this with a triangle diagram, such as the version shown in Figure 1.
Here, for every 600 unsafe acts 30 near misses are likely to occur, 10 minor injuries and one major injury. The U.S. Bureau of Labor statistics reports 2,236 work-related fatalities in 2017 due to falls, contact with objects and equipment, exposure to harmful substances or environments, and fires and explosions. In the same year, workers experienced 882,700 injuries that caused them to miss work afterward.
OSHA, the Occupational Safety and Health Administration, provides standards for injury prevention. Industry management generally takes care to provide a safe environment for workers. This includes safety guarding and other prevention mechanisms and policies, but intentionally overriding safety features or operator mistakes or negligence can result in the unfortunate statistics on injury and fatalities. Heinrich suggested the vast majority of injuries were due to human failure of one form or another. How and why does this happen?
Any machine or process can injure someone if it is mishandled. Protective measures are required by law and by good practice. Such safety protections for mechanical hazards include barrier guards, two-hand operated devices and electronic interlock devices.
Anywhere there is a guard, an employee may intentionally seek to defeat it or unintentionally fail to engage it. For the guards and protections to do their job, operators and management must do their part. Why would they not?
WHAT LEADS TO UNSAFE ACTS?
Various conscious and unconscious personal attitudes and behaviors might motivate individuals to circumvent safety features or commit other unsafe acts.
Attitude and Personality: In studying attitude, two of its functions are revealed: a self-defensive function and a social-adjustive function. The self-defensive function motivates the operator to try to maintain his/her self-image as a tough worker by avoiding safety guards. The social-adjustive function makes the worker liable to follow the behavior of others in the peer group who engage in unsafe acts. In addition, a phenomenon of “immunization” may occur, where a worker who has limited exposure to the consequences of hazards does not accept the safety rules. Most industries face this problem, where an attitude issue or lack of awareness may cause workers to reject or resist safe practices in the workplace and discount the good reasons to use safety guards and other safety devices and follow safety procedures.
Human Error: The different kinds of human errors include slips, lapses and mistakes. Slips and lapses have been characterized as skill-based errors, or errors of execution. A slip might be an unintentional action, such as opening a valve when intending to tighten it. A lapse represents an error of memory, such as forgetting to do something, or completing steps in the wrong order.
Mistakes may be described as failures of planning, grouped into two types: rule-based and knowledge-based. A rule-based mistake occurs where a bad rule is followed, or a good rule is misapplied or ignored. Knowledge-based mistakes come from a lack of understanding of a mechanism or process, often in a trial-and-error situation, where insufficient knowledge results in a solution that is expected to work, but doesn’t.
Performance Pressure: Line managers sometimes promote unsafe behaviors in order to reduce cycle time or otherwise optimize the available resources. For example, in a warehouse, a worker might stack pallets beyond the recommended limit, resulting in risk of slippage and injury. Such activity can become regarded as normal if it is continued over time and under pressure to increase production or finish a job on time, for example.
Work-Related and Technical Problems: The safety guards in a workplace are sometimes bypassed in order to get the work done. Operators may justify this by blaming the management for providing inappropriate guards that obstruct them from doing their job. In one incident reported by Mike Taubitz, senior advisor at FDR Safety, a worker was injured by a robot while working to set it up. At the time, the interlock was bypassed that was supposed to prevent power to the robot if someone entered the robot enclosure. When asked if the setup task could be done without power, the worker replied, “No.” In this case, the safety interlock would prevent the worker from doing his job. The task needed to be redesigned so it could be performed safely.
Some accidents do occur due to mechanical or technological failures, such as an incident reported by OSHA that happened in a food processing plant. Employees were performing a normal cleaning process for a fryer. The computer control failed to maintain the correct temperature in the fryer, allowing the temperature to rise excessively. This caused an increase of steam pressure, which caused one of the fryer panels to blow out, splashing one employee with hot cleaning solution and resulting in second- and third-degree burns on his back.
OTHER FACTORS THAT AFFECT ATTITUDE AND BEHAVIOR
Shift Work and its Consequences: Shift work goes against workers’ circadian rhythm, which affects them biologically. When the internal biological clock is disturbed due to the patterns of shifts, the workers lose attention and sometimes experience fatigue and depression.
Supervision and Teamwork: Unfortunately in many incidents reported, supervisors or team leaders do not give proper instructions or they promote unsafe acts for the increased productivity. Also, individuals can be affected both positively and negatively by a team’s culture.
Personal and Social Stressors: All workers are bound by their family situations and affected by their relationships. When they carry problems from outside into the workplace, organization rules and regulations may not seem so important to them.
Lack of Skills, Training or Education: New workers and others who do not understand the purpose and importance of safety guards, devices and procedures may not use them properly. Management and co-workers can help new staff to understand the organization’s safety policies.
RECOMMENDATION: DEVELOP A BEHAVIORAL SAFETY PROGRAM
Just as total quality management (TQM) demands a culture of quality from all the individuals in the organization, a behavioral safety program also requires participation of all employees to provide a safe environment. In order to develop a behavior-based safety program, the organization can follow a procedure similar to the following.
- Form a team to address the issues.
- The team investigates the behaviors causing the deviations or unsafe acts, perhaps using a checklist to aid in observation.
- The team solicits feedback and suggestions about current procedures and possible improvements.
- The team creates objectives and a plan to improve the organization’s safety culture.
- The team develops metrics to track safety, such as number of accident-free days accumulated, number of unsafe acts per month, or safety suggestions per month.
- Finally, the organization puts the plan into place and then tracks the metrics on a continuing basis and revisits the safety situation when needed.
Of all these steps the most important one is giving and receiving feedback. After most incidents, supervisors or team leaders tend to avoid negative statements in order to maintain a healthy relationship with subordinates. However, leaders do need to strongly reinforce the possible consequences of non-compliance so employees understand the importance of following safety procedures. The behavioral factors for doing unsafe acts because of personality, attitude, team-work culture and other factors can be dealt with using this approach.