Proactive Prevention: Part Three of our back-to-basics series on worker safety examines a safety philosophy based upon engineering injuries out of a process during the design stage when it is far less costly.
This article is the third in a series about the basics of worker safety. Last month we looked at the safety philosophy driving Behavior-Based Safety. Now we turn our attention to its biggest competitor: Process-Based Safety, or simply “Process Safety” as it is more commonly known, a safety philosophy rooted in engineering, process improvement, and the belief that injuries are symptomatic of a larger system flaw.
Process Safety begins by examining a workflow and identifying inputs, transformations, and output. Any unwanted output – from scrap to worker injuries – is considered waste. Waste elimination is central to process improvement, as waste consumes resources but adds nothing of value. Process Safety capitalizes on process improvement to lower the risk of worker injuries.
A key element of Process Safety is the idea that injuries should be engineered out of a process. Proponents of Process Safety point out that the greatest opportunity to ensure that a process is safe is at the beginning of the design stage, and that this control perspective and likelihood of success greatly diminishes over time (see Figure 1). They also argue that it is far less costly to make changes to a process during the design stage than it is after the process is in production.
Process Safety emphasizes a proactive approach where a safety strategy is used to anticipate areas where a process failure is likely to result in worker injuries. The governing concept of Process Safety is that the best way to reduce injuries is to anticipate, identify, and eliminate the hazards most likely to cause injuries. This emphasis on proactive prevention manifests in workplace inspections where hazards (both physical and behavioral) are identified and contained until they can be completely corrected.
Since proponents of Process Safety believe that system flaws cause injuries, injuries are investigated using root cause analysis. In root cause analysis, the cause of an injury is traced to a system flaw that is then addressed.
Because Process Safety advocates believe that worker mistakes are inevitable, they typically insist that, whenever possible, controls must be added to the process to ensure that no one is harmed by these mistakes. The somewhat-misleading term “mistake proofing” is often used to describe this process. An essential tool used in mistake proofing is the Hierarchy of Controls, which ranks the order of the methods used by safety professionals to reduce the risk of worker injuries (see Figure 2). These controls are arranged in a pyramid to denote the most effective at the top of the pyramid with successively less effective controls arranged beneath these it.
According to Process Safety advocates the most effective method of keeping workers safe is elimination, the practice of removing the hazard completely, typically through process reengineering. This practice, while exceedingly effective, is not always possible or practical, so safety professionals then move to the next most effective control: substitution. Applying the substitution control involves removing the hazard and replacing it with a less risky alternative.
As with elimination, it is sometimes impossible or impractical to use a less hazardous material, so the safety professional would then move to engineering controls as the next effort to protect workers. Engineering controls are typically physical devices used to prevent workers from coming in contact with hazards, such as machine guards, light curtains and other devices that either prevent the worker from accessing the hazard or cut the power (including electrical, fluid, air, and gravity) and restrict the movement of machine components that might otherwise injure workers.
In some cases, none of these controls are effective enough to protect workers. In these situations safety professionals must rely on the two controls that are least effective, but better than no protection at all. The first of these are administrative controls that include safety training, safety policies, and rules designed to protect the workers. The weakness of administrative controls is that their effectiveness relies on the active cooperation of the workforce complimented by discipline/enforcement. Too often the variability endemic to human behavior renders administrative controls ineffective.
The lowest and least effective control is the use of personal protective equipment (PPE). While PPE is an important part of worker safety, it is fraught with weaknesses. Chief among these weaknesses is that the use of PPE is heavily dependent on the willing and active cooperation of the workers themselves. Many workers resist the use of PPE because it is often uncomfortable and may actually make the work more difficult to perform.
Another element of central importance to Process Safety is data trending and analysis. Process Safety proponents collect leading and lagging indicators to gage the effectiveness of safety initiatives and to anticipate changes in risk. This trend analysis is often used to drive strategic changes and modifications in safety policies and procedures.
Process Safety is not without its critics. Safety professionals from other schools of thought contend that Process Safety ignores worker behaviors as a primary cause of most injuries and deride Process Safety advocates as trying to “bubble wrap the world.” Opponents of Process Safety claim that attempts to design safety into a process are laudable, but such activities are seldom completely successful and, in those cases, it is too costly and impractical to retrofit equipment to make its operation safe after it has been built.
Still others claim that Process Safety fails to hold workers accountable for unsafe work practices, recklessness or gross negligence, and that a blame-free approach to worker safety does not adequately address worker culpability in injuries.
Process Safety advocates answer these criticisms by arguing that it is always more cost effective to proactively avoid injuries than to react to injuries once they have occurred. Further, they argue, that since no one actually wants to get hurt or gets hurt deliberately, behavior-based approaches are far more costly and less effective than the process-based approach. They also counter that Process Safety does not ignore safety, but that it focuses on the causes of unsafe acts and poor decision making, rather than trying to modify worker behaviors.
The debate between proponents of Process Safety and the advocates of BBS is often contentious and heated, but neither approach has all the answers and both approaches have serious limitations.
Next month, a look at Just Culture.
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