- Author
- Heskestad, G. | Delichatsios, M. A.
- Title
- Environments of Fire Detectors. Phase 1. Effect of Fire Size, Ceiling Height and Materials. Volume 2. Analysis.
- Coporate
- Factory Mutual Research Corp., Norwood, MA
- Sponsor
- National Bureau of Standards, Gaithersburg, MD
- Report
- NBS GCR 77-95; FMRC Serial 22427, July 1977, 129 p.
- Distribution
- Available from National Technical Information Service
- Contract
- GRANT-69001
- Keywords
- ceiling height | ceilings | cotton | detector location | fire detectors | fire growth | heat detectors | polyurethanes | polyvinyl chloride | smoke detectors | smoldering fires | temperature rise | wood
- Abstract
- This volume is an analysis of experimental data presented in Volume 1 on the ceiling environment and response to this environment by various types of fire detectors. Data and the analysis pertain to flat, extensive ceilings and quiescent surroundings. The results for smoldering fires are found to be of limited utility because of dominant influence of uncontrolled variables such as pre-existing temperature stratifications; however, an anomalous smoke pattern has been explained, which should aid future investigations. The results of environmental variables versus time for the unsteady, flaming fires are found to correlate very well in coordinates which intrinsically account for variations in fire-growth rate and ceiling height. Hence, ceiling temperatures and velocities can be predicted as function of time for any combination of fire-growth rate and ceiling height. Optical densities for a given combustible material are found to be in approximately constant ratio to the local temperature rise. In flaming fires smoke detectors are found to respond at approximately constant temperature rise of the fire gases; this temperature rise depends on the combustible material and mode of fire spread. The response of heat detectors is shown to be predictable theoretically from the temperature and velocity fields and key detector characteristics. The final section of the report deals with spacing requirements of fire detectors in flaming fires as influenced by ceiling height, fire-growth rate, and detector characteristics. The results are presented in graphical and tabular forms.