Current through Register Vol. 54, No. 45, November 9, 2024
Section 50.43 - Classification(a)NFPA Standard. Interior finish materials shall be classified in accordance with NFPA Standard 255, tests of surface burning characteristics of building materials, 1979 Edition as listed in this section.(b)Class A Interior Finish. Flame Spread 0-25 includes any material classified at 25 or less on the test scale. Any element thereof when so tested shall not continue to propagate fire.(c)Class B Interior Finish. Flame Spread 26-75 includes any material classified at more than 25 but not more than 75 on the test scale.(d)Class C Interior Finish. Flame Spread 76-200 includes any material classified at more than 75 but not more than 200 on the test scale.(e) Exposed portions of structural wood members complying with the size requirements in § 50.11(c) (relating to construction tables) shall not be considered interior finishes.