Investigation of Cable and Cable System FireTest Parameters:Task B —Firestop Test Method (NUREG/CR-4112, US 75-1,Volume 2)

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Publication Information

Manuscript Completed: December 1984
Date Published:
January 1985

Perpared by:
Underwriters Laboratories Inc.
333 Pfingsten Road
Northbrook, IL 60062

Prepared for:
Division of Engineering Technology
Office of Nuclear Regulatory Research
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

NRC FIN B-6197

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An experimental investigation was conducted to provide data concerning the effects that changes in pressure differential, fire exposure and sample construction have on firestop performance when exposed to a standard fire test. Fifty-one fire test experiments were conducted using pressure differentials between -12 to +120 Pa, different sample constructions and two fire exposure conditions. Findings were that small changes in pressure differential did not have a significant effect on firestop materials that did not have cracks or through openings to allow passage of gases during fire exposure. If the materials allowed passage for gases through cracks or holes, such as those left open after pulling a cable, changing the pressure differential affected the firestop performance. Also, it was demonstrated that changing the size of the opening; size, location and type of the penetrating items installed through the opening; and severity of fire exposure affected the performance of the firestop.

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