Richard A Licht

US Patent:

43642101, Dec 21, 1982

Filed:

May 29, 1980

Appl. No.:

6/154456

Inventors:

Peter B. Fleming - Woodbury MN
Richard R. Licht - New Richmond WI
Joseph C. Peisert - St. Paul MN

Assignee:

Minnesota Mining and Manufacturing Company - Saint Paul MN

International Classification:

E04B 548

US Classification:

52221

Abstract:

Penetrations or passageways through fire resistant walls, floors, partitions and ceilings are frequently necessary to provide for present or future pipes, cables or conduits. A device fixed to the walls of the penetration provides a barrier to prevent the passing of fire, heat, smoke and toxic gases, and water through the penetration under adverse conditions of fire or elevated temperatures. The device includes at least one end cap capable of providing a cold smoke seal. An intumescent material which in the event of excessive heat or fire, foams and expands to substantially fill the penetration, is provided. The device may include a laminated restraining layer to provide assurance that the char formed during the intumescent reaction to fire and heat, is generated so that the penetration cavity is optimally filled.