- Author
-
Bill, R. G., Jr.
|
Stavrianidis, P.
|
Hill, E. E., Jr.
|
Brown, W. R.
- Title
- Water Mist Fire Protection in Residential Occupancies. Technical Report.
- Coporate
- Factory Mutual Research Corp., Norwood, MA
- Sponsor
- Fire Administration, Washington, DC
- Report
-
FMRC J.I. 0Y1N9.RA,0Z0J1.RA
November 1994
91 p.
- Contract
- EMW-94-C4447
- Keywords
-
water mist
|
fire protection
|
residential buildings
|
nozzles
|
fire tests
|
sprinklers
|
reliability
|
costs
|
test facilities
|
standards
|
residential sprinklers
- Abstract
- The capability of impingement type water mist nozzles, with operating pressures lower than 1.2MPa, to provide fire protection for residential occupancies was investigated in sixteen fire tests. In these tests, four different nozzle models were evaluated. Two of the nozzles were commercially developed. The flows for the two commercial nozzles were 15.5 lpm and 29.5 lpm when operated at 1 MPa and 0.8 MPa, respectively. The other two nozzles investigated were prototypes operating at comparable flows and pressures. The higher flow nozzles were installed at a 1.4 m spacing from the walls (2.4 m between nozzles) in fire tests, while the other nozzles were installed at a 1.2 m spacing from the walls (1.5 m between nozzles). The fire tests were conducted in a room 5.5 m x 5.5 m with openings to two adjacent rooms (and in one test, an opening to a corridor). The fuel packages used in the fire tests were the corner residential fuel packages of Underwriters Laboratories (UL) and the Factory Mutual Research Corporation (FMRC), a bedroom fuel scenario, a kitchen fuel scenario, a shielded heptane pool fire, and the UL and FMRC fuel packages along a wall between two sprinklers. Of the four nozzle models investigated, only the commercial nozzle with the lowest single nozzle flow (15.1 lpm) was deemed acceptable for residential occupancies. In six fire tests in which the nozzles were installed with a 79ºC temperature rated actuating bulb, a maximum of three nozles operated. The mist system using these nozles operated with a total water supply of 45 lpm. The total water supply requirements were, therefore, slightly less than the requirements for sprinklers designed for limited area dwellings, and significantly less than requirements for residential sprinklers (~70 to 100 lpm). Recommendations for approval testing and installation standards have been made. Fire testing indicated that the UL corner residential package provided a more severe challenge than the FMRC corner test with the mist nozzles employed as tested in this study. Therefore, the UL corner residential fire test has been incorporated in recommended approval testing. However, in a comparison between the UL and the FMRC corner residential tests, in which prototype Limited-Water-Supply sprinklers were installed, the FMRC residential package was found to provide a more severe challenge. The reliability of a mist system, compared to a residential sprinkler system, is discussed along with cost considerations.