Fire Damper Ratings

DOE-STD-1066-99

14.4.1.2 Door openings into 1-hour rated filter plenum housings should be 3/4-hour

minimum fire-rated.

14.4.2 Fire Damper Ratings

14.4.2.1 Listed 1 1/2-hour fire rated dampers should be installed where ventilation

ducts, not required to continuously function as part of a confinement system,

penetrate 2-hour fire rated construction.

14.4.2.2 Fire dampers are not required when ducting penetrates 1-hour fire rated

construction. The duct should pass through the wall and extend into the

area to be considered. The areas on either side of the wall should be

completely protected by automatic sprinklers in order to eliminate the

dampers. Transfer grills and other similar openings without ducting should

be provided with an approved damper.

14.4.2.3 Fire dampers in duct work should not be utilized when penetrating the fire

rated construction where the ducting is an integral part of the nuclear air

filter system equipment that is required to continuously function as part of

the confinement system. Such duct material penetrating fire rated

construction without fire dampers should:

o be made part of that fire-rated construction by either wrapping,

spraying, or enclosing the duct with an approved material, or by other

means of separating the duct material from other parts of the building

with equivalent required fire-rated construction; or

o be qualified by an engineering analysis for a 2-hour fire-rated exposure

to the duct at the penetration location where the duct

maintains

integrity at the duct penetration with no flame penetration through the

fire wall after a 2-hour fire exposure. (See Appendix D for a discussion

of this type of analysis.)

14.4.2.4

Dampers in the air cleaning system for the purpose of controlling pressure,

direction, or volume of air flow and for isolation of filters during change out

or inspection are permitted in the ventilation system.

14.4.3

Other Penetrations and Openings in Fire-Rated Enclosures

All mechanical and electrical penetrations made into fire-rated plenum enclosures should

be fire stopped by listed materials meeting the requirements of ASTM E-814 with a fire

rating not less than the rated enclosure.

14.5 Materials and Special Hazards Inside Plenums

14.5.1

Combustibles Located Inside Filter Plenum Enclosures

Filter plenum enclosures should only be used for ventilation control equipment. The

storage and accumulation of combustible materials as well as combustible and flammable