Page 207 - Structural Steel Designers Handbook AISC, AASHTO, AISI, ASTM, and ASCE-07 Design Standards

Brockenbrough_Ch04.qxd 9/29/05 5:09 PM Page 4.35

BUILDING CODES, LOADS, AND FIRE PROTECTION*

BUILDING CODES, LOADS, AND FIRE PROTECTION 4.35

2400 1315.6

2200 1204.4

2000 1093.3

1800 982.2

1600 871.1

1400 760.0
Degrees F 1200 645.9 Degrees C

1000 537.8

800 426.7

600 315.6

400 204.4

200 93.3

−17.8
0 1 2 3 4 5 6 7 8
Hours
FIGURE 4.7 Variation of temperature with time in the standard fire test specified in ASTM E119.
(Source: American Society for Testing and Materials, Conshohocken, Pa., with permission.)

the “standard fire.” Thus fire-resistance requirements are expressed in terms of hours. The design of
free-resistant buildings is typically accomplished in a prescriptive fashion by selecting tested
“designs” that meet specific building code requirements.
It is emphasized that ASTM E119-based fire-resistance ratings are comparative in nature.
They are conducted on idealized laboratory specimens and are not intended to be a predictor of
structural performance of actual buildings in real fires. Special nonstandard fire tests may be
desirable in some cases.
Listings of fire-resistance ratings for construction assemblies are available from a number of sources:

• Fire-Resistance Directory, Underwriters Laboratories, Northbrook, Ill.
• Fire-Resistance Ratings, American Insurance Services Group, New York, N.Y.
• Fire-Resistance Design Manual, Gypsum Association, Washington, D.C.

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