- Author
-
Lee, A.
- Title
- Audibility of Smoke Alarms in Residential Homes.
- Coporate
- Consumer Product Safety Commission, Washington, DC
- Report
-
CPSC-ES-0503,
September 2005,
54 p.
- Keywords
-
smoke detectors
|
fire alarm systems
|
residential buildings
|
effectiveness
|
noise (sound)
|
fire hazards
|
fire codes
|
adults
|
elderly persons
|
human response
|
horns
|
signals
|
fire tests
|
bedrooms
|
corridors
|
kitchen fires
|
NFPA 74
|
NFPA 72
- Identifiers
- human response to sound pressure and pitch; auditory arousal from a smoke alarm; piezoelectric horns used in residential smoke alarms; smoke alarm signal; smoke alarm performance; measuring sound loss in one- and tow-family dwellings; estimating sound loss in residential homes
- Abstract
- The U.S. Consumer Product Safety Commission (CPSC) staff initiated an evaluation in 2003 to review the audibility effectiveness of smoke alarms in residential homes. In this report, sound loss of a smoke alarm signal as it travels in a home is examined to determine the impact this may have on alerting occupants to a fire hazard. Sound loss measurements of smoke alarm signals in actual homes are compared to sound levels required to alert adults (without hearing or other impairment). The CPSC staff conducted sound loss measurements in three different test homes using single station smoke alarms. The homes were built between 1960 and 1989. The sizes of the homes ranged from approximately 1,000 square feet to 3,300 square feet. The homes had either two or three levels. Measurements were taken with doors closed and opened. The CPSC staff tests of sound loss measurements indicated that a single station smoke alarm installed in a small, single-level home may be sufficient to alert occupants, even if the bedroom doors are closed. The sound level effectiveness of an alarm in a single-level home with larger square footage may be reduced. For a two-level home, sound levels may not be sufficient to alert occupants in all areas of the home or cause a delay for some individuals to respond immediately. In CPSC staff tests, an alarm traveling from one level of a home to another and through a closed door produced sound levels around 50 dBA, which would be at the lowest level for awakening an unimpaired adult with no background noise present. Single station smoke alarms installed in a three level home may not be sufficient to alert occupants in all areas of the home. In CPSC staff tests, an alarm traveling from the basement to the second floor and through a door produced sound levels around 30 dBA, which would most likely not awaken an unimpaired adult, even with no background noise present. Smoke alarms in homes are effective in alerting occupants only if the sound can be heard. The complexity of the path that the sound must travel plays an important role in the resultant sound level. A home with narrow hallways, turns, and multiple levels results in lower sound levels throughout the home compared to a home with an open floor plan and fewer turns.