What is the maximum door size for ITS/WHI fire rated doors?

ITS/WHI is "Warnoch Hersey". ITS/WHI is the formal designation for Intertek Testing Services / Warnock Hersey. ITS/WHI is an independent agency with testing, listing, in-plant inspection, and labeling capabilities.

Maximum ITS/WH Fire Rated door sizes are as follows:

L-Series:

1. 4' 0" X 10' 0" single door
2. 8' 0" X 10' 0” double door or pairs

SL-Series:

1. 3' 0" X 8' 0" single door
2. 6' 0" X 8' 0" double door or pairs

Maximum doors size for Fire ratings is influenced by (but not limited to) the following items:

1. Steel gage of the door - example: 20 gage door constructions are approved for smaller door sizes than what is shown above.
2. Frame applications - some frame applications are approved for smaller door sizes than what is shown above.
3. Hardware applications - some hardware applications are approved for smaller door sizes than what is shown above.
4. Glass sizes, glass type and glazing compound.

NOTE: The following door constructions are not listed ITS/WHI Fire Doors A-Series, B-Series, CE-Series, H-Series, T-Series