The National Fire Protection Agency (NFPA) created NFPA 70E, a Standard for Electrical Safety in the Workplace. The goal of NFPA 70E is to protect electrical safety workers around any device capable of generating arc flash, and provides recommended safety practices for industries involved in the installation, repair and maintenance of electrical systems. The 70E Store, LLC provides the below information as a high level overview. Your best source for complete information on the NFPA 70E Standard is via the actual standard, available for purchase at www.nfpa.org.
In 2000, the NFPA 70E Standard first addressed electric arc flash hazard and required flame resistant arc flash clothing to protect workers. The current edition of the NFPA 70E standard was released in 2004, and further details personal protective equipment. Although compliance is voluntary, OSHA recognizes the standard, and has referenced it in citations.
The NFPA 70E Standard details six levels of Hazard Risk Categories (HRC) [see table 1.1], also called “Levels”. The greater the risk: the higher the HRC. Arc Rating can be either ATPV or EBT. Arc Rating is the incident energy on a fabric that results in sufficient heat transfer through the fabric to cause the onset of a second-degree burn. EBT is reported when ATPV cannot be measured due to FR fabric breakopen. A hazard risk assessment should be performed by a qualified hazard risk assessor to determine the risk level, and thus, the necessary level of compliance to the 70E standard. The 70E standard provides additional details on assessing your hazard risk for job tasks. Once the Hazard Risk Category has been determined, the necessary protective clothing can be purchased.
Table 1.1 Adapted from 2004 NFPA 70E table 130.7(C)(11)
Protective Clothing Chart
Hazard Risk Category (HRC)
Required minimum Arc Rating of PPE cal/cm2
0
N/A
1
4 cal/cm2
2
8 cal/cm2
2*
8 cal/cm2*
3
25 cal/cm2
4
40 cal/cm2
* Includes head and face protection.
The 70E Store clearly denotes the Hazard Risk Category and the arc rating / ATPV for each of its arc flash clothing products. If you need additional information about a product, contact us.