Hazard elimination is the most effective risk control method, according to NFPA 70E Informative Annex F Table F.3, and can be accomplished by the creation of an electrically safe work condition (ESWC). All employers must establish, document and implement an ESWC policy that requires hazard elimination to be the first priority in the implementation of safety-related work practices.

The employer must also document how it will comply with the general rule for establishing an ESWC and the exceptions that follow, which recognize justified energized work. The ESWC policy can be documented in the employer’s electrical safety program required in Section 110.3, or in the employer’s management system or similar documentation. 

Creating an ESWC

An informational note following 110.2(B) sends the standard user to sections 120.2 through 120.6 for requirements to establish and verify an ESWC for the time the state is maintained. The general rule [110.2(B)] requires an ESWC be created before an employee performs work, including where the employee will be within the limited approach boundary (LAB), or before an employee interacts with equipment where conductors or circuit parts are not exposed, but there is an increased likelihood of injury from an exposure to an arc flash hazard. 

Work within the LAB is easy to determine. A LAB exists only where there are exposed energized electrical conductors or circuit parts, which is easy to determine because we can see them. Assuming work at or equal to 50V and not exceeding 750V, the limited approach boundary is 3 feet, 6 inches. If an employee will be within this boundary, the general rule is to create an ESWC. 

The determination of interaction with equipment where an increased likelihood of arc flash exists is determined by applying Table 130.5(C). For example, where an employee is racking a low-voltage power circuit breaker (LVPCB), they are interacting with the equipment in a manner that increases the likelihood of an arc flash.

The employer’s policy is required to address each of the exceptions that follow the general rule to establish an ESWC. These exceptions prescriptively identify tasks considered justified energized work. Where an employee is or could be exposed to shock or arc flash hazards, risk assessments must be performed and documented. In some cases, an energized electrical work permit (EEWP) will be required and must also be documented. 

Exceptions

The employer’s ESWC policy is not required to but could direct the need for documentation of risk assessments and EEWPs where the justified energized work thresholds [exceptions No. 1 through No. 5 following 110.2(B)] are addressed. Normal operation of electric equipment is permitted [110.2(B) Exception No. 1] if the conditions in all seven list items are met. 

This exception serves a critical role in the standard. Normal operation of electrical equipment occurs constantly, for example, opening and closing SWD/HID molded-case circuit breakers (MCCB) used to switch lighting daily. However, normal operation does not come with an easy button. In all cases, the employer must consider the likelihood of occurrence and potential severity. 

Consider, for instance, the operation of two circuit breakers without a likelihood of an arc flash incident as each are in a normal operating condition: a 20A MCCB presents a low potential severity and a 2,000A frame LVPCB as a service disconnect at 480/277V has a high potential severity. 

Normal operation of equipment is not identified as being exempt from the need for an EEWP. The second justified threshold [110.2(B) Exception No. 2] permits the operation of an energized disconnecting means or isolating element to create an ESWC after a risk assessment is performed. 

The third justified threshold [110.2(B) Exception No. 3] permits energized work where the employer can demonstrate that the task is not feasible in a de-energized state due to equipment design or operational limitations. This exception is task-driven and permits performing diagnostics and testing, including start-up or troubleshooting of electric circuits that can only be performed with the circuit energized. Risk assessments are needed but not an EEWP. 

The fourth justified threshold [110.2(B) Exception No. 4] permits energized work where the employer can demonstrate that de-energizing introduces additional hazards or increased risk. For example, the shutdown of hazardous location ventilation equipment would create additional hazards. This threshold is venue- or occupancy-driven. This is a difficult circumstance for the employer. Risk assessments and an EEWP would be required in all cases. 

The last justified threshold [110.2(B) Exception No. 5] addresses energized electrical conductors and circuit parts operating at less than 50V and permits energized work where an assessment is performed and determined that there will be no increased exposure to electrical burns or to explosion due to electric arcs. 

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