What Can I Do With Incident Energy Studies?

By Cole Ferguson

Today, I will outline three things you can do with a completed incident energy study. Completing these tasks is an important part of any electrical safety plan, and will reduce the risks to employees performing work on energized equipment. This will also reduce the risk of an arc flash incident occurring.

Identify Key Problem Areas

An incident energy study will show you where the incident energy is dangerously high in your facility. Now that you know the incident energy on a particular bus is high, you can analyze your power system with this information in mind, and try to answer the following two questions:

  1. Why is the incident energy at this location so high?
  2. Can the incident energy at this location be lowered somehow to provide a safer working environment?

Establish Working Boundaries and Select Warning Labels

An example of a warning label

Once you've answered the questions about your key problem areas, you might determine that the incident energy level cannot be reduced any farther. From here, what you can do is use the information in your incident energy study to establish safe working boundaries and acquire warning labels. The incident energy study should indicate the likelihood of an arc flash event occurring. Knowing the risks, you can assign appropriate working boundaries for the tasks involved with energized equipment. The incident energy study should have different "levels" assigned to each piece of equipment that is a part of the study. These levels correspond to recommended working distances, and you can use these levels to label all of your equipment so that every worker understands the risks of working on energized labelled equipment.

Select Appropriate PPE For the Job

Now you can use your newfound knowledge of the safe working boundaries to select the appropriate PPE for any job that takes place in your facility.

Determine working boundaries can also be used to determine PPE requirements. If for example you must work closer than the recommended working boundary, the incident energy study will recommend the level of PPE required for doing energized work at different working distances.

In order to determine what PPE you need, you'll have to use the relevant standards. CSA Z462 in Canada and NFPA 70E in the USA both have extensive tables describing what appropriate PPE is for the various levels of incident energy on a work site. It is important to also adhere to any and all local and regional standards for your area.

An incident energy study is required for determining safe working boundaries and PPE for the work site.