In discussions with electrical contractors from all over the country that implement NFPA 70E in the workplace, questions usually involve the potential for missing key elements in the arc flash risk assessment. Each assessment is different; there is no cookie-cutter approach.

The good news is that most of the industry has embraced safe work practices. However, we can always improve. Electrical safety is a shared responsibility and a work in progress. We must continuously audit and monitor the status and effectiveness of our electrical safety programs (ESPs).

Obviously, perfection is unattainable. Arc flash risk assessments are estimations. An incident energy analysis is a prediction (see the Article 100 definition), and Section 130.7(C)(15) clarifies that available fault current and clearing time values are estimated.

Risk assessment

In the scope of Article 130, which addresses work involving electrical hazards, the last paragraph mandates that without regard to the method used in an arc flash risk assessment, all requirements in Article 130 apply. Many wonder why the technical committee added such text. The reason is simple—we become familiar with the method chosen (incident energy analysis or the arc flash PPE category method) and are tempted to settle for a mediocre assessment, so we sometimes go on autopilot. Familiarity breeds complacency.

For example, qualified persons may just identify the incident energy exposure on a label or identify an arc flash PPE category, choose the required PPE and perform the task without any attention to other critical elements. There is much more to a comprehensive risk assessment.

The operating condition of the upstream overcurrent protective device (OCPD)—and its condition of maintenance—must be determined. In many cases, employees forget that more than one risk control method in the hierarchy of risk control may apply. Once it is determined that energized work is justified and necessary, employees may turn to PPE, and in many cases, nothing else. When applying the hierarchy of risk controls, substitution lends itself well to the design stage, but not with existing equipment. The application of engineering controls must always be considered, including, but not limited to, remote switching, remote racking, arc energy reduction methods (as required in the National Electrical Code) and guarding energized electrical conductors and circuit parts. The number of qualified persons needed to safely perform the task must also be determined.

Risk control methods awareness and administrative controls are not nearly as effective as engineering controls, but should not be overlooked. Signs alerting others of potential hazards and a determination of all applicable employer procedures and job planning tools is important. See Informational Note No. 1 that follows the general rule in 110.3(A) mandating that the employer implement and document an overall ESP that directs activity appropriate to the risk associated with electrical hazards. It explains that proper maintenance and installation, alerting techniques, auditing requirements and training requirements provided in NFPA 70E are administrative controls and part of an ESP. These controls must be considered in each risk assessment.

Auditing

Auditing is a critical component in monitoring the effectiveness of the overall ESP. Section 110.3(L)(2) mandates that all field work be audited annually to verify that the requirements in the ESP’s procedures are followed. This documentation includes, but is not limited to, every shock/arc flash risk assessment (required in 130.4(D) and 130.5(D)) and all energized electrical work permits (EEWPs).

It is quite common for qualified persons to not document assessments when troubleshooting as an EEWP is not required. Each employer must address this through training and feasible methods to document risk assessments. Paper documents could be easily created, but methods such as the risk assessments on the Safety Meeting App walk the qualified person through each step and then documents assessments in the cloud.

Other protective equipment must be considered (130.7(D)) such as insulated tools, ladders and fish tapes. Barriers are also a requirement. Exposed energized electrical conductors or circuit parts operating at 50V or more must be guarded by a barrier in accordance with 130.7(D) to prevent unintentional contact while an employee is working within the restricted approach boundary of those conductors or circuit parts.

Section 130.8 contains requirements for other precautions, but due to its location in the back of Article 130, it is often overlooked. These precautions require that the risk assessments address alertness, employee impairment such as fatigue, changes in scope (which leads to a significant amount of incidents), blind reaching, additional illumination, wearing conductive items such as jewelry, doors and hinged panels that can swing into an employee, clear spaces, confined spaces, housekeeping tasks, flammable materials, anticipating failure, routine opening/closing of circuits, reclosing circuits after OCPD operation, safety interlocks and alerting techniques.

Take the time to ensure you are getting arc flash risk assessments right.

stock.adobe.com