These doors are labeled and classified by warnock hersey international inc as fire barriers in sizes up to and including 4 0 x 8 0.
Warnock hersey fire doors asbestos.
I seem to remember the old super six going from asbestos to fibre cement in the mid 70 s not much knowledge on fire doors though mmmmmm just googled super six up and it stopped asbestos in 1985 but i m pretty sure i never used it in the late 70 s.
There are two asbestos fiber classifications.
Contains hard spiky crystals along with a range of colors like brown blue and green.
Doors are capable of meeting the requirements for both positive and neutral pressure fire tests including ubc 7 2 1997 ul 10c 1998 nfpa 252 1995 astm e 152 1982 and ul 10b 1997 including the hose stream.
Intertek s warnock hersey mark is a mark certifying product safety and performance used in north america including on wood fire rated doors.
This mark is widely recognized throughout the industry appearing on fire doors and frames found in north america and beyond.
Asbestos is a group of naturally occurring non combustible silicate minerals composed of glass like fibers.
Intertek s warnock hersey mark has long been one of the industry s most recognizable marks and is found on a variety of products including fire doors and frames.
The warnock hersey mark can be found on more than 6 500 products ranging from fire doors hardware hearth plumbing and construction products.
Fire doors rails are approximately 5 8 on top and 1 3 4 on bottom.
Contains chrysotile or soft white asbestos.