The contact heat rating measures the gloves material exposure to temperatures between 100ºC (212ºF) and500ºC (932ºF). The length of time is then measured for how long it takes the inside material temperature to increase by 10ºC (18ºF) from the starting temperature. 15 Seconds is the minimum accepted length of time for approval. CAUTION: EN407:2004 rated contact heat resistant gloves will reduce the risk of injury but not prevent burns if used beyond the recommended temperatures or contact time. Users should always use caution when handling hot materials. Be familiar with the protection needed for your intended application. CLC Work Gear disclaims any liability for claims arising out of product misuse or improper application.