Finish Rating 2
Finish Rating 2 :
The time in minutes, determined under specific laboratory conditions, at which the stud or joist in contact with the exposed protective membrane in a protected combustible assembly reaches an average temperature rise of 121°C (250°F) or an individual temperature rise of 163°C (325°F) as measured behind the protective membrane nearest the fire on the plane of the wood. NFPA 921, 2004 ed. Fire. A rapid oxidation process, which is a chemical reaction resulting in the evolution of light and heat in varying intensities. NFPA 921, 2004 ed. Fire Alarm Signal. A signal initiated by a fire alarm-initiating device such as a manual fire alarm box, automatic fire detector, waterflow switch, or other device in which activation is indicative of the presence of a fire or fire signature, (see Figure f. 2). NFPA 72, 2002 ed
