What is IEC 61482?
This standard is designed for clothing meant to protect the wearer from the electrical arc against thermal dangers.
The standard for protective clothing protecting the wearer of the electrical short circuit against thermal dangers. For work in areas where electrical arcs are frequent, the standard is relevant. When working directly with transformers, cables, electrical boxes or domestic booths, the arc energy potential is 240 kJ to 500 kJ or more. In some cases, the energy input is higher than class 1 or 2 (box arc test).
IEC 61482 -1-1
In the United States, this test method is used. This test procedure measures the ATPV or EBT50 value. The ATPV value is the (cal / cm2) value that predicts that 50% of protection from a second burn will be achieved. Greater the value, the better the protection, the fabric offers. In America, for employees exposed to electric arc hazards a minimum ATPV value of 8 is required. The ATPV is indicated on the label.
The “box” test is used in Europe IEC 61482-1-2. A sample for fabric is exposed to a 4kA (Class 1) or 7kA (Class 2) short circuit generated electric arc. In the test, the heat transmitted by the sample is measured during and after the test. The amount of heat is transmitted by the sample. Based on the resultant data and the STOLL curve, it is then determined the length of time required for the onset of second-degree burns. In Europe, 61482-1-2: test “box” is used (the testing method is compared to 50354). It is also assessed for postfire, hole formation, melting, etc. A complete jacket must be tested in addition to fabric samples. The goal is not to assess the energy value but rather to evaluate the jacket for defects in the seams, fastenings and all other accessories following exposure to an electric arc. The requirements set out in this standard apply to the welding model requirements (EN ISO 11611).
Design requirements by IEC 61482
All seams shall be tested for flames under IEC 61482-2 In order not to come into direct contact with the skin of the wearer, all the metal components, like the buttons, zips, etc. shall be covered on the outside or inside the garments of the wearer. The wearer should not be burned or melted, nor should buttons, zips or other accessories increase the risk of burning. The garment must be open after an electric arc and without any melted or burnt components, the inside of the garment must be fully intact. Long sleeves must be on the garment covering the upper body part. During all working operations, two-piece wear requires at least a 20 cm overlay between the jacket and the pants. Clothing materials shall be made from flame-retardant materials. The material should not ignite or shrink and not exceed 5%.
Open arc test of IEC 61482
Part 1-1, Test Method 1: The arc rating of flame retardant material or clothing (ATPV or EBT50) is determined by this test. In the same open-arc test, both ATPV and EBT are evaluated. The first result is the arc rating reported, which is in cal/cm2. If the material has a higher value of thermal isolation in relation to heat than the arc strength, the material will first be opened. If not, the material will be burnt before it opens. The lowest is the one used to mark the garments. None is better than the other alternative. In essence, EBT is more isolated than strong, and ATP is less insulated than strong.
The EBT usually means that the wearer’s garment is knitted and more comfortable, but no less protective. You should never decide on which protective clothing you should wear based on the ATPV or EBT rating of the clothing. They are more regarded as functional partners. The Arc Thermal Performance Value (ATPV) is the incident energy on a substance that gives a 50 percent chance of causing second degrees based on the Stoll Curve arc measuring in cal/cm2, due to adequate heat transfer. The higher the value is, the better the safety.
The Breakopen energy threshold (EBT) is incident energy in a material that gives the chance to break open by 50 percent. The open break is defined by a minimum of 1.6 cm2 open area. The greater the value, the greater the safety.
Tests can be performed on single or multiple material layers, both ATPV and EBT. You get a higher value when testing multiple layers than if testing the material separately. This is because of the isolation and protection effects of air trapped between materials.
Standards like IEC 61482 are meant to ensure quality standards of safety wear of the industrial workers who deserve the best protection of their life and limb.