The IEEE published a new standard procedure for “determination of the ampacity derating factor for fire-protected cable systems.” IEEE 848-2015 provides a test procedure for use in establishing the ampacity derating factor for cables installed in fire-protected conduits, trays, free-air drops, cable penetration fire stops, or electrical separation wrap systems. The new standard is available for purchase on the IEEE’s website.
Description*
“This standard provides a test procedure for determining the ampacity derating factor in the following cable installation configurations: Block-out or sleeve-type cable penetration fire stops; Conduits covered with a protective material; Trays covered with a protective material; Cable directly covered or coated with a fire-retardant material; Free-air drops enclosed with a protective material. The standard is applicable to cables installed and sized to IEEE Std 835(TM) for conduits and free-air
*Description from IEEE website.