Document Archives

Concrete Masonry Fire Resistance Ratings

• ID:

  86

• ESCSI:

  3220.045

• Author:

  Not Given

• Publication Name:

  Concrete Masonry Fire Risistance Ratings

• Type of Publication:

  Article

• Publisher:

  National Concrete Masonry Association

• Dated:

  1962

• Issue/Volume:

  November

• Other ID:

  NCMA, 9/2/64

• Page(s):

  1-4 incl. illus

• Reference List:

  N

• Abstract:

  Fire-resistance ratings of concrete masonry walls are based on fire tests made at Underwriters’ Laboratories, Inc., National Bureau of Standards, Portland Cement Association, and other recognized laboratories. In the test, one face of the wall is exposed to a fire of controlled severity for a time period equal to or greater than its rated fire=resistance time. Immediately following, the hot face of the wall is subjected to a fire-hose stream. Bearing walls also carry a load during the test equal to 80 psi based on gross wall area. Walls must withstand the fire test without passage of flame or gases, must limit heat transmission to less than 250°F gain in temperature, and must withstand the thermal impact of a fire-hose stream immediately following the test.It is not economically feasible to conduct a fire test on every assembly of concrete masonry materials an architect might design for each project. Therefore, it is desirable to have a rational method of design which agrees with existing data. Two alternatives are available.
  The two alternatives are estimated fire-resistance ratings and certified masonry units. Comments on both alternatives are found in the article.