Electrical Risk Assessment

An electrical risk assessment and an arc flash risk assessment comprise an electrical risk assessment.

To begin, how is risk defined? The National Fire Protection Association's standard for electrical safety in the workplace, NFPA 70E 2021, defines risk as the combination of the likelihood of occurrence and the severity of injury or damage to health caused by a hazard. There are two major dangers associated with electricity: shock and arc flash. Each hazard necessitates a thorough examination of each situation and task. The risk assessments are intended to provide answers to the following questions:

• Is there a hazard present?
• Is it likely that an injury will occur?
• How serious is the potential injury?
• How is the risk mitigated in accordance with the risk control hierarchy?
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Shock hazard: A shock hazard is defined as a potential source of injury caused by contact with/approach to exposed and energized electrical conductors or circuit parts. The limited approach boundary is also defined in 70E as the distance from exposed and energized parts where a shock hazard exists. Consider the following questions: A) Do we have exposed and energized parts (over 50 volts), and will we cross the limited approach boundary? If this is the case, there is a risk. B) Is it likely that an injury will occur? The restricted approach boundary is where there is a higher risk of injury. Injury is likely if this distance is crossed. The voltage determines the severity. Voltages above 50 volts can cause fatal or disabling injuries. In general, the higher the voltage, the higher the current.

Finally, choose an appropriate risk-mitigation strategy based on the risk-control hierarchy. Consider the following as an example of a simplified approach: Can we create an electrically safe work environment after our hazardous energy control procedure (or lockout/tagout procedure)? If not, may we leave? If not, can a different voltage be substituted? Can we put something between us and the hazard if not? If none of that holds true, we may need to use personal protective equipment.

Arc flash hazard: The likelihood of occurrence is determined by the interaction between the employee and the energized equipment, and 70E Table 130.5(C) can assist in this determination. When a hazard exists, the likelihood of injury is centered on being inside the arc flash boundary, and severity is determined by performing incident energy analysis or using the PPE category tables in 70E. The final piece, however, remains: Can I create an electrically safe working environment? Can I remain silent? Can I fill in? Can I put something between us? If not, PPE can be used to reduce the severity of the injury to a level that allows it to be survived.

Performing both risk assessments are critical to employee safety from electrical hazards. Keep in mind that both must also consider equipment design and condition of maintenance, as these factors can greatly affect results. However, once we understand the nature of the danger we’re exposed to, we can take effective steps to mitigate the risk and work safely.