NFPA 253 Standard Method of Test for Critical Radiant Flux of Floor Covering Systems Using a Radiant Heat Energy Source
NFPA 253 使用辐射源测试地板覆盖材料的临界辐射通量的方法
1-1.1 This fire test response standard describes a procedure for measuring critical radiant flux behavior of horizontally mounted floor covering systems exposed to a flaming ignition source in a graded, radiant heat energy environment within a test chamber. The specimen can be mounted over underlayment or over a simulated concrete structural floor, bonded to a simulated structural floor, or otherwise mounted in a typical and representative way.
1-1.2 This fire test response standard measures the critical radiant flux at flameout. It provides a basis for estimating one aspect of fire exposure behavior for floor covering systems. The imposed radiant flux simulates the thermal radiation levels likely to impinge on the floors of a building whose upper surfaces are heated by flames or hot gases, or both, from a fully developed fire in an adjacent room or compartment. The standard was developed to simulate an important fire exposure component in fires that develop in corridors or exitways of buildings and is not intended for routine use in estimating flame spread behavior of floor covering in building areas other than corridors or exitways. Appendix F provides information on the proper application and interpretation of the results of this test.
1-1.3 This standard shall be used to measure and describe the response of materials, products, or assemblies to heat and flame under controlled conditions and shall not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, the results of the test shall be permitted to be used as elements of a fire hazard assessment or a fire risk assessment that takes into account all factors that are pertinent to an assessment of the fire hazard or fire risk of a particular end use.
1-1.4 This standard does not purport to address all safety problems associated with its use. The user of this standard is responsible to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. Specific safety precautions are provided in Chapter 4.
For the most accurate measurement of critical radiant flux, use the testing procedures outlined in the 2011 NFPA 253.
Advance knowledge about how materials react to fire is critical to making informed selections. Referenced by NFPA 101® Life Safety Code® and building codes as the test procedure used to determine the critical radiant flux of a material, NFPA 253 Standard Method of Test for Critical Radiant Flux of Floor Covering Systems Using a Radiant Heat Energy Source is a test method that is designed to provide a basis for estimating one aspect of the fire exposure behavior of a floor covering system installed in a building corridor or exitway.
Update to the 2011 edition to stay on top of important changes including
· Added tolerances to dimensions to create harmonization between NFPA 253, ASTM E 648, and ISO 9239-1
· New provisions on laminate specimens
· Revised criteria for specimen size and mounting as well as test reporting requirements
Valuable Annexes discuss how to calibrate an apparatus, mounting methods, sample data logs, proper application and interpretation of results, specific safety precautions, and more. (Softbound, 18 pp., 2011)
