Safety: Incident Prevention in our Industry and Beyond

Safety: Incident Prevention in our Industry and Beyond


By Randall H. Miller, Director of Research, Development and Industry Intelligence

Safety is a moral issue. There is no business worth asking people to sacrifice their health, physical ability or lives. People work to help provide for themselves and their families, and contribute to society. Serious work injuries not only potentially degrade victims’ quality of life but also hamper their ability to work. In extreme cases, that may mean people end up becoming dependent on the family for whom they had been providing and the community to which they had once contributed.

Safety managers make a distinction between accidents and incidents. The term accident is in disfavor because it implies that outcomes are due to fate or bad luck, which safety managers consider to be a counterproductive message. Rather, industrial safety teaches us that injuries are not random and are avoidable. Consequently, unplanned, undesirable events that could result in unintentional injuries referred to as incidents.

From an economic perspective, incidents have a negative effect on a company’s bottom line as they generate compensation claims and medical costs. Worse, those costs account for only about 20 percent of industrial injury expenditures, which increase due to higher insurance premiums, lost production, training of replacements and other financial liabilities. Those costs inhibit a contractor’s ability to compete and a utility’s capacity to keep rates under control.


Incidents can be attributed to unsafe acts and unsafe conditions. Unsafe acts include human error, willful rule violation and maliciousness. Equipment failure is an example of an unsafe condition. Unsafe acts, such as willful rule violation and maliciousness cannot be tolerated and should be subject to discipline. Human error is more difficult to manage because most people average five errors an hour and can only concentrate on two or three things simultaneously. However, supervisors can plan for and prevent most unsafe conditions. Equipment failure should be minimized through regular inspections and maintenance. Providing workers with the appropriate, protective equipment and making sure they wear it reduces injury severity if an incident occurs.

It is important to distinguish between unsafe acts and conditions. For example, a consulting utility forester neglecting to wear a high visibility vest is committing an unsafe act, while an employer failing to provide the vest is creating an unsafe condition. The point is that both employees and employers share responsibility in creating and maintaining a safe work environment.

Behavioral-Based Safety

Industrial safety was pioneered in the 1930s by Herbert Heinrich, who initiated research, which resulted in behavioral-based principles of accident prevention that are still in use (Heinrich, Peterson and Ross 1980). Heinrich found that 88 percent of all industrial accidents (Heinrich used the term accident) are caused by people committing unsafe acts, with the reminder attributable to unsafe working conditions. Heinrich reached the common sense conclusion that the more frequently workers are unsafe, the greater the chance they will have an accident. In fact, he determined that for every serious injury or fatality, there are scores of minor injuries, hundreds of close calls and thousands of unsafe acts.

Heinrich concluded that the best way to prevent serious or fatal accidents is to eliminate unsafe acts and conditions. He illustrated the concept with an accident pyramid (Figure 1). His example was comprised of untold thousands of unsafe acts or conditions at the base of the pyramid, leading to 300 close calls, 29 minor injuries and ultimately one major injury or fatality at the top. Heinrich’s precise ratio of one major accident for every 29 minor accidents and 300 close calls should not be viewed as a scientific law, but an example. Accepting unsafe acts contribute to a counterproductive culture characterized by what Jacobs (2012) calls normalization of deviance.

In a 2012 Tree Care Industry Association article, McClenahan advanced Heinrich’s theories, describing the unsafe acts and close calls at the bottom of the pyramid as a safety program’s leading indicators, and serious injuries or fatalities as lagging indicators. McClenahan modified Heinrich’s triangle, putting prevention-based systems at the base, classifying close calls, workplace errors, and first aid cases under $100 as leading indicators, OSHA recordables under $500 as transition cases, and lost time injuries to be lagging indicators (Figure 1). While he endorses incident investigation to obtain lessons learned from lagging indicators, he agrees with Heinrich that it is far more effective for safety programs to prevent incidents in the first place, and recommends proactively using lessons learned from leading indicators to do so.

 The Blame Game

Sometimes supervisors misunderstand the point of behavioral-based safety and use it as justification to over rely on discipline to reduce unsafe acts. However, that can be counterproductive because it implies that bad things happen to bad people, and those bad people deserve punishment. While that might work in the short term, it is a shortcut that can undermine morale and create a mistrustful work environment. Ultimately, it compromises safety programs by discouraging employees from coming forward to report close calls out of fear of reprisal. As a consequence, retaliatory programs lose the opportunity to fully benefit from lessons learned, including identifying latent circumstances and conditions that can lead to injuries. Furthermore, over reliance on discipline diverts employer’s from their responsibility to prevent unsafe conditions.

 Multiple Causation

Multiple causation is a refinement of the behavioral-based safety theory (Peterson 1997). The philosophy maintains that Heinrich oversimplifies reality. Proponents of the multiple causation theory consider workplace injuries to be caused by a number (rather than the number) of contributing factors and causes, which randomly interact. Prominent among these factors and causes is exposure to serious conditions. Rather than simply reducing the overall frequency of unsafe acts, safety managers should direct their attention to those circumstances that are most likely to result in severe injuries. For example, debilitating injuries are far more likely to occur to workers at height in proximity to high voltage lines than they are to those completing production reports. Supervisors should not misdirect their energy on benign activities when their effort would be better spent addressing behavior and conditions on potentially more threatening jobs.

McClenahan (2012) advances multiple-causation theory by prioritizing risk factors through a modification of a risk assessment matrix (Figure 2). The modification categorizes unsafe acts on the basis of the probability they would cause an incident and the likely severity of the event’s consequences. The approach can be used to evaluate where managers should focus their energies. For example, a frequently occurring unsafe act with catastrophic potential consequences (serious injury or death) would carry extreme risk and should draw close attention. On the other hand, there are probably other areas to apply efforts than the isolated acts with negligible severity. That is not to say those unsafe acts should be ignored, just not emphasized. McLenehan advises that the technique provides a systematic approach to establishing feedback loops, trend analyses and resource allocations. He also councils companies to maintain the criteria that are already best for their company culture, and not to waste time focusing on areas of known high compliance.

McLenehan (2012) advises using job behavior observations and perception surveys to collect the leading indicators. He asserts that successfully applying this information carries the following benefits:

  • Targeted training programs to address “real” issues within an organization
  • Training can advance beyond compliance only-based required programs
  • Training can be geared toward operational efficiency and valuable results can be attained
  • Data can be combined with lagging-indicator data to strengthen employee development programs
  • It provides an early-warning system
  • It provides metrics for employee performance beyond the dollars and cents of a job

 Creating a Culture of Safety

Organizations should create a culture of safety. A safety culture integrates the employers’ responsibility (unsafe conditions) and worker responsibility (unsafe acts) with behavior-based safety training. It is a belief system that the most important goal of every work day is for everyone to return home safely. It is both learned and taught, and has to involve every team member from senior management to the newest worker. That means everyone has to be a leader and mentor, and to be approachable with both positive and negative feedback (Nutter 2012).


Employers have a moral responsibility to provide a workplace free of known hazards. Behavioral-based industrial safety principles were pioneered in the 1930s by Herbert Heinrich. While they have been modified by Peterson (1997), McClenahan (2012) and others, the underlying principles of Heinrich’s work remain true today. Heinrich reached a conclusion that the more frequently a labor force works unsafely, the greater the chance they will have (what he called) an accident. Heinrich concluded that the best way to prevent serious or fatal incidents is to eliminate unsafe acts and conditions. He illustrated the concept with an accident pyramid in an example comprised of untold thousands of unsafe acts or conditions at the base of the pyramid, which led to hundreds of close calls, tens of minor injuries, a number of serious injuries and ultimately a fatality at the top. The idea is that by the time an organization experiences a serious injury or fatality, their workforce had already experienced a number of serious incidents. They had been working their way up the pyramid. A series of close calls over a short period is a wake-up call that something is amiss within the company’s safety program and unless identified and corrected may result in injuries.

Work organizations have to create a culture of safety that involve everyone from senior management to the newest worker. That means everyone has to be a leader and mentor, and to be approachable with both positive and negative feedback.


Anonymous. 2012. UAA Safety Meeting. Utility Arborist Newsline.

Heinrich, H.W., D. Petersen and N. Roos. 1980. Industrial Accident Prevention. Fifth Edition. McGraw-Hill Book Company. New York, NY.

Jacobs, Pat. 2012. Achieving compliance with the Law and Company Rules. Utility Arborist Newsline. 3(1):30.

McClenahan, V. 2012. Management Exchange: Risk Management: Utilization of Leading Indicators in the Continuous Improvement Cycle. Tree Care Industry. XXIII(11):68-72.

Nutter, W. 2012 Safety Culture. Utility Arborist Newsline. 3(1):26-28.

Peterson, D. 1997. Behavior-Based Safety Systems: A Definition and Criteria to Assess. Professional Safety. January 1, 1997.

Peterson, D. 2001. Safety Management: A Human Approach. Third Edition. American Society of Safety Engineers. Des Plaines, IL







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