Arc Thermal Performance Value (APTV) is the rating assigned to Flame-Resistant Clothing which indicates the level of protection provided. It is measured in calories per centimeter squared (cal/cm2).

Breakopen Threshold Energy (EBT) is the rating given to Flame-Resistant Clothing that indicated the level of protection provided. It is used when ATPV (see above) cannot be measured because the fabric breaks open. The energy causing the break open is expressed as the EBT.

High Vis Clothing
Any clothing that has highly reflective properties or a color that easily stands out from any background. High vis clothing may also have reflective stripes.

Hazard Risk Category (HRC) is the rating range directly related to ATPV. Please see the HRC chart for category hazard risk ratings. (can this be a link to a chart?)

The National Electric Safety Code (NESC) is the standard used by electric utilities to implement safety procedures for utility workers.

NFPA 70E is the world standard published by the National Fire Protection Association (NFPA®). This standards recommends that you wear flame resistant clothing of your job entails work with, on or around energized equipment (motors, circuits, breakers, etc)–wherever there is a possible exposure to electric arc flash.

OSHA 29 CFR 1910.269
This is the only federal law relating to FR clothing for electrical purposes, and covers the operation and maintenance of electric power generation, control, transformation, transmission and distribution lines and equipment.