Protective Clothing against the Thermal Hazards of an Electric Arc
IEC 61482 ARC FLASH PROTECTION
Under this standard there are two test methods as defined below:
IEC 61482-1-1:2009 ‘Open Arc’ Test Method (ATPV test and garment test).
This standard replaces IEC 61482-1:2002 and is the same as the original North American method for measuring the Arc Thermal Performance Value (ATPV), as used in ASTM F1959.
Materials or assemblies are given an ATPV value, expressed in kilojoules per square metre (kJ/m2), which can be converted into the familiar cal/cm2. IEC 61482-1-2:2007 ‘Box Arc’ Test Method (Fabric classification and garment test).
The ‘Box arc’ test method is based on the original European method described in ENV 50354, with a heat transfer measurement.
Materials or assemblies are classified as Class 1 (4 kA) or Class 2 (7kA). During this test, a fabric sample is exposed to an electric arc produced by a 4kA or 7kA short circuit. The amount of heat transmitted through the sample is measured during and after the test. The resulting data determines the length of time it would take to cause the onset of second-degree burns. Samples are also assessed for after-flaming, hole formation, melting, etc.
The result is divided into four PPE categories, also known as HRC or Hazard Risk Category.
PPE 1 – 4-8 cal/cm2
PPE 2 – 8-25 cal/cm2
PPE 3 – 25-40 cal/cm2
PPE 4 – >40 cal/cm2
we recommended that your outer layer reaches at least 8 cal/cm2 (i.e. PPE / HRC Category 2).