CFPS Exam Dumps : Certified Fire Protection Specialist (CFPS)

Critical radiant flux is used to classifyinterior floor finishes. Critical radiant flux is a measure of the minimum radiant heat energy required to sustain flame propagation on a floor material or covering. It is determined by exposing a specimen to a radiant heat gradient and observing the distance from the ignition point to the flame-out point.The shorter the distance, the higher the critical radiant flux and the better the fire performance of the floor material or covering1.Critical radiant flux is used to classify floor materials and coverings according to their fire hazard and resistance, and to specify the minimum requirements for different occupancies and applications2.For example, the International Building Code (IBC) requires that interior floor finishes and coverings in exit access corridors and exit enclosures have a critical radiant flux of not less than 0.45 W/cm2, while those in other spaces have a critical radiant flux of not less than 0.22 W/cm23.Critical radiant flux is also used to evaluate the fire safety of floor materials and coverings in transportation vehicles, such as aircraft, trains, and buses4.

Cellulose nitrate products begin to decompose at about 300 °F (150 °C). This is the temperature at which the nitrate ester bonds start to break down and release nitric acid, which further catalyzes the decomposition. The decomposition temperature depends on the nitrogen content, the stabilizers, and the external heating rate of the cellulose nitrate. Higher nitrogen content, lower stabilizer concentration, and faster heating rate lower the decomposition temperature and increase the risk of thermal runaway.

References:Nitrocellulose - Wikipedia;Comparative analysis of stable decomposition and combustion kinetics of nitrated cellulose;Degradation of aged nitrocellulose investigated by thermal analysis methods;Nitrocellulose;Effect of stabilizers and nitrogen content on thermal properties of nitrocellulose

Fire alarm systems audible appliances ratings are usually stated as a sound pressure level (SPL) at 10 ft (3.05 m) from the appliance. The SPL is measured in decibels (dB) and indicates the loudness of the sound produced by the appliance. The SPL at 10 ft (3.05 m) is used as a standard reference point for comparing different audible appliances and for designing fire alarm systems to meet the required audibility levels.References:

• NFPA 72: National Fire Alarm and Signaling Code, 2019 Edition, Section 18.4.3.11
• Fire Protection Handbook, 20th Edition, Volume 1, Chapter 7, Section 7.8.2.12