The testing requirement for the T rating involves placing a number
of thermocouples on the unexposed side of the assembly.
Thermocouples are placed on the backside of the penetrating
item, on the firestopping material and on the wall or floor assembly.
T Rating is measured as the amount of time taken by any of the
thermocouples on the unexposed side to exceed a temperature rise
of 325 F (180 degree C) above its initial temperature. Therefore the
T rating is an indication of how long all the unexposed surfaces stay
below the temperature rise limits.
F RATING
• PREVENT FLAME PASSAGE
• MAINTAIN STRUCTURAL INTEGRITY
(HOSE STREAM TEST)
T RATING
• TEMPERATURE RISES
• F RATING CRITERIA
THROUGH PENETRATION
FIRESTOPS
(Fig 2.8 F Rating and T Rating)
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