A Global View of Electric Arc Standards
General 08 Oct 2020
Those who work in the industrial environment face multiple threats. In this instance, we’ll focus on intense electric-related hazards, specifically electric arcs. During an electric arc, temperatures can reach up to 35,000°F, or 20.000°C (that’s hotter than the surface of the sun), so wearing the proper flame retardant (FR) PPE is paramount. Let’s take a look at how you can help make sure your team is up to standard and adequately protected—and how your location globally plays a critical role in doing just that.
Chances are, you’ve come across definitions of both FR fabrics and FR/AR fabrics (flame retardant arc rated). But what’s the difference? The short answer: all arc rated fabrics are FR, but not all FR fabrics have been arc rated. Arc rated fabrics have been tested for protection against an electric arc exposure and have an arc rating that indicates the level of incident injury it will protect you against. Prior to the use of the term FR/AR, the NFPA 70E standard only required arc rated fabrics to be tested for flame-retardant. Now arc fabrics are required to be tested for both flame-retardant and electric arc protection. The electrical industry standards all over the world require workers to dress in arc rated PPE, and in this blog we are going to break down two of the main global electric arc standards—IEC 61482-2 and NFPA 70E.
Outide of the United States, IEC 61482-2 is the international standard that specifies fabric and garment certification requirements for protecting workers against electric arc hazards. Under IEC 61482-2, PPE should be tested and certified using one or both of following methods:
- IEC 61482-1-1: Open Arc Test Method
- Provides the arc rating of the fabric or garment in cal/cm2 (ATPV or EBT50—whichever is lower).
- IEC 61482-1-2: Box Test Method
- Determines the arc protection class rating (class 1 or 2) of the fabric or garment using a constrained and directed electric arc.
IEC 61482-2-tested and certified garments will be identified by the pictogram below, marked by either the arc rating or arc protection class:
(Replaced in 2018) (Established in 2018)
All FR/AR garments in the EU must also be CE-marked per EU PPE Users Directives (89/656).
NFPA 70E is the United States standard for policies and protocols designed to safeguard employees faced with the threat of electric arcs. This includes ASTM F1506, which is the standard NFPA 70E cites for fabric and garment testing and certification.
- Per ASTM 1506, ASTM F1959 (or F1959M for FR fabric) is the test method used to determine the arc rating (ATPV or EBT50). This is the same open arc method used in IEC 61482-1-1.
- Once the arc rating of the fabric is determined, a garment can be evaluated in an electric arc exposure to also test the finished product using ASTM F2621.
Under NFPA 70E, all PPE receives an incident energy level determined by the fabric or garment’s arc rating from the ASTM test method. There are four PPE categories stating the minimum arc rating required to meet each level—beginning with Cat 1 which has the lowest minimum arc rating of 4 cal/cm2. The subsequent three PPE categories have minimum arc ratings set at 8, 25 and 40 cal/cm2. Per OSHA standard and NFPA regulation, compliant clothing has the ATPV or incident energy level identified on the garment label.
|NFPA (USA)||IEC (Outside of the US)|
|Overarching Standard||NFPA 70E||IEEE 1584|
|Garment Certification||ASTM 1506||IEC 61482-2|
|Protection Level Test Methods||ASTM F2621 ASTM F1959/F1959M for FR Fabric||IEC 61482-1-1 IEC 61482-1-2|
The main difference between these two standards is that IEC 61482-2 utilizes a 2-level classification system while NFPA 70E relies on 4 levels of incident energy categorization.
Help navigating the global landscape
Many companies operate in various regions around the world, which can require seeking out additional information to find the right solution for your team. Our technical experts at Westex comply with a range of industry standards and are here to help answer your questions and navigate what products are best for your needs. We engineer an extensive number of fabrics—including FR cotton, blends and aramid fabrics—that are tested and certified to global standards, and guaranteed flame retardant for the life of the garment. We’re always here to help and always ready to work with you to find the right solution—contact us.