- Author
-
Braun, E.
|
Davis, S.
|
Klote, J. H.
|
Levin, B. C.
|
Paabo, M.
- Title
- Assessment of the Fire Performance of School Bus Interior Components. Final Report.
- File
-
get_pdf.cfm?pub_id=916735
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Sponsor
- Department of Transportation, Washington, DC
- Report
-
NISTIR 4347,
July 1990,
177 p.
- Distribution
- Available from National Technical Information Service
- Keywords
-
buses
|
cone calorimeters
|
seats
|
flame spread
|
furniture calorimeters
|
combustion products
|
smoke
|
tenability limits
|
toxicity
|
large scale fire tests
|
small scale fire tests
- Identifiers
- fire performance; ignitability; rate of heat release; school buses
- Abstract
- Since seat assemblies represent the single largest type of combustible fuel in a school bus interior, this study is limited to currently used and state-of-the-art material assemblies. Six different seat assemblies having a range of fire performance were examined. Small-scale tests (Cone Caloimeter, LIFT, and NBS Toxicity Protocol) were performed on these materials. Large-scale tests (Furniture Calorimeter) were conducted on single seat assemblies. Full-scale tests were performed using a simulated bus enclosure measuring 2.44 m wide by 2.13 m high by 8.23 m long and three seat assemblies. The impact of ignition source size was determined by computer simulation. It was found that a 500 kW ignition source could produce untenable thermal conditions in the simulated bus enclosure. Seat assemblies were exposed to 50 kw and 100 kw ignition sources in the large-scale tests and 100 kW ignition source in the full-scale tests. It was found that the small-scale tests were unable to provide a simple method for material selection that was consistent with the full-scale test results. At the present time, small-scale fire tests of materials cannot be depended upon to predict the fire behavior in the real world. Therefore, based on the full-scale test results, a generalized full-scale test protocol for seat assembly evaluation was developed that combines full-scale testing in an enclosure with an analysis protocol that determines the time-to-untenable conditions. The procedure defines the conditions under which toxicity testing would be necessary. Full-scale test instrumentation and material orientation are also described.