Fire Mitigation Design and Practices

DOE-HDBK-3010-94

Appendix B; Plutonium Recovery Facility

2.1.5.3 F ire M itigation D esign an d P ractices

Whenever possible, construction materials are noncombustible or fire resistant. As

previously noted, the exterior walls and roof of the building are cast-in-place concrete having

a minimum 3-hour fire rating. The concrete interior walls and gypsum board over steel stud

walls have minimum 2- and 1-hour fire ratings, respectively. Major structural components

of the gloveboxes and process material are made of noncombustible material. Where

potentially combustible shielding has been used, such as Benelex, it is coated with

intumescent paint to minimize chances of ignition in all but the most severe fires.

Flammable liquids are not allowed in gloveboxes as part of the combustible loading control

program in effect. Potentially combustible wipes are limited by this program as well to

approximately 10 in line at any one time, a number normally associated with shutdown

cleaning in the gloveboxes as opposed to processing. In normal operation, non-installed

combustibles in the operating areas are limited to operator logs and procedure manuals.

When maintenance on gloveboxes is in progress, tent construction material is made of fire-

resistant materials.

The major potential sources of fixed combustibles, aside from Benelex shielding on certain

gloveboxes, are electrical wiring and glovebox gloves. Wiring is installed in accordance

with appropriate codes and housed in conduits or sealed raceways. Wiring penetrates

gloveboxes through pave connectors to prevent an insulation fire from progressing into

gloveboxes. The glovebox gloves are made of materials such as Hypalon and will melt and

burn at elevated temperatures. However, the number of gloves is limited, and storage of

used gloves in a line after removal is forbidden by procedure.

2.1.5.4 F ire D etection an d A larm S ystem

The plant has three types of fire detectors available: ionization, photoelectric, and thermal.

All three are used in individual processing rooms, while only thermal detectors are used in

gloveboxes and ventilation plenums. Exceeding the setpoint on any detector will initiate an

alarm in the operating area, the facility control room, and the site fire department. Failure

of a detector and interruption of signal flowpath by such means as a wire break will initiate

an alarm as well.

2.1.5.5 F ire S u p p ression S ystem

All areas of H Plant are equipped with automatic wet-pipe sprinklers in the overhead that

actuate at temperatures slightly higher (approximately 155 F) than the fire detection alarm

setpoints. A dedicated set of thermal detectors in gloveboxes and rooms are used to provide

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