CFPS Exam Dumps : Certified Fire Protection Specialist (CFPS)

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

The minimum carbon dioxide design concentration for extinguishment of an ethylene fire is43%. This is based on the cup burner method, which is a standard test to determine the flame extinguishing concentration of a gaseous agent for a liquid fuel. Ethylene is a flammable gas that can form a liquid under pressure. The cup burner method involves placing a liquid fuel in a metal cup with a central nozzle, and flowing a gaseous agent through the nozzle to create a diffusion flame. The gaseous agent is gradually increased until the flame is extinguished.The minimum concentration of the gaseous agent required to extinguish the flame is recorded as the flame extinguishing concentration1.According to a study by NIST, the flame extinguishing concentration of carbon dioxide for ethylene was found to be 43%1.This value is also consistent with the NFPA 12 standard, which specifies the minimum design concentrations of carbon dioxide for various fuels, including ethylene2.