After the first five risk controls have been implemented and there is a residual hazard or risk of injury, the sixth and final risk control provides the last option to limit the severity of an injury from the known and present hazard. The hierarchy of risk controls is:
(3) Engineering controls
(4 ) Administrative controls
(6) Personal protective equipment (PPE)
PERSONAL PROTECTIVE EQUIPMENT (PPE)
The use of personal and other protective equipment is the least effective of the risk controls and is the last line of defense when an incident happens. PPE is used when there is a hazard which presents a risk of an injury to an employee performing a justified task. PPE has an impact on limiting the severity of an injury but has no impact on the hazard or on the likelihood of an incident. The equipment being worked on can be damaged and an arc-flash can occur. In such an incident, the employee could suffer an injury albeit a nonpermanent, recoverable injury when the appropriate PPE is properly used.
Successful use of this control is directly impacted by human effort. A human must properly use the PPE category or incident energy method to determine the level of hazard. A human must select appropriate PPE including the proper rating and must refrain from purchasing substandard or counterfeit PPE which can increase the severity of injury to the employee. A human must correctly don or use the PPE. A human may not understand the need for PPE, PPE may create a barrier to the effective completion of their work, a human may specify PPE inappropriate for the hazard, and a human may neglect to use PPE when needed. Each of these instances can defeat this protection method.
However, PPE is the final opportunity to limit the severity of injury when a hazard exists and an employee must interact with the equipment. When establishing an electrically safe work condition, the PPE should (hopefully) never need to prevent an injury but it is there in case something goes wrong in the process. When an employee is performing justified energized work, the PPE is protecting the employee from an exposed hazard and when an incident occurs should limit their injury.
The hierarchy of risk controls must be applied when using either of the risk assessment methods (PPE category or incident energy analysis). Regardless of the intent to require the establishment of an electrically safe work condition or to justify energized work, the hierarchy of risk controls must be implemented to minimize the hazard or risk of injury. Often a combination of controls is necessary to achieve the desired result. It may not be possible to utilize every control for a given situation. The goal of NFPA 70E is protecting an employee from an electrical injury. The hierarchy of risk controls guides you through steps that can provide a more safe work environment for your employee or at least minimize the risk or severity of an injury.
Next time: A revisit to exemptions to the work permit.