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Smoke and CO Detectors

 


It’s important to have enough smoke alarms in your home. Fire research has demonstrated that with today’s modern furnishings, fires can spread much more rapidly than in the past when more natural materials were used. Because of this, having a sufficient number of properly located smoke alarms is essential to maximize the amount of available escape time. For many years NFPA 72, National Fire Alarm and Signaling Code, has required as a minimum that smoke alarms be installed inside every sleep room (even for existing homes) in addition to requiring them outside each sleeping area and on every level of the home. (Additional smoke alarms are required for larger homes.) Homes built to earlier standards often don’t meet these minimum requirements. Homeowners and enforcement authorities should recognize that detection needs have changed over the years and take proactive steps make sure that every home has a sufficient complement of smoke alarms.

Installing smoke alarms
  • Choose smoke alarms that have the label of a recognized testing laboratory.
  • Install smoke alarms inside each bedroom, outside each sleeping area and on every level of the home, including the basement.
  • On levels without bedrooms, install alarms in the living room (or den or family room) or near the stairway to the upper level, or in both locations.
  • Smoke alarms installed in the basement should be installed on the ceiling at the bottom of the stairs leading to the next level.
  • Smoke alarms should be installed at least 10 feet (3 meters) from a cooking appliance to minimize false alarms when cooking.
  • Mount smoke alarms high on walls or ceilings (remember, smoke rises). Wall-mounted alarms should be installed not more than 12 inches away from the ceiling (to the top of the alarm).
  • If you have ceilings that are pitched, install the alarm within 3 feet of the peak but not within the apex of the peak (four inches down from the peak).
  • Don't install smoke alarms near windows, doors, or ducts where drafts might interfere with their operation.
  • Never paint smoke alarms. Paint, stickers, or other decorations could keep the alarms from working.
  • For the best protection, interconnect all smoke alarms. When one smoke alarm sounds they all sound. Interconnection can be done using hard-wiring or wireless technology.
  • When interconnected smoke alarms are installed, it is important that all of the alarms are from the same manufacturer. If the alarms are not compatible, they may not sound.
  • There are two types of smoke alarms – ionization and photoelectric. An ionization smoke alarm is generally more responsive to flaming fires, and a photoelectric smoke alarm is generally more responsive to smoldering fires. For the best protection, both types of alarms or combination ionization-photoelectric alarms, also known as dual sensor smoke alarms, are recommended.
  • Keep manufacturer’s instructions for reference.

Testing smoke alarms
  • Smoke alarms should be maintained according to manufacturer’s instructions.
  • Test smoke alarms at least once a month using the test button.
  • Make sure everyone in the home understands the sound of the smoke alarm and knows how to respond.
  • Follow manufacturer’s instructions for cleaning to keep smoke alarms working well. The instructions are included in the package or can be found on the internet.
  • Smoke alarms with non-replaceable 10-year batteries are designed to remain effective for up to 10 years. If the alarm chirps, warning that the battery is low, replace the entire smoke alarm right away.
  • Smoke alarms with any other type of battery need a new battery at least once a year. If that alarm chirps, warning the battery is low, replace the battery right away.
  • When replacing a battery, follow manufacturer’s list of batteries on the back of the alarm or manufacturer’s instructions. Manufacturer’s instructions are specific to the batteries (brand and model) that must be used. The smoke alarm may not work properly if a different kind of battery is used.
 

Interconnected smoke alarms increase safety

In a Consumer Product Safety Commission (CPSC) survey of households with any fires, including fires in which the fire department was not called, interconnected smoke alarms were more likely to operate and alert occupants to a fire.1 People may know about a fire without hearing a smoke alarm.

  • When smoke alarms (interconnected or not) were on all floors, they sounded in 37% of fires and alerted occupants in 15%.
  • When smoke alarms were not on all floors, they sounded in only 4% of the fires and alerted occupants in only 2%.
  • In homes that had interconnected smoke alarms, the alarms sounded in half (53%) of the fires and alerted people in one-quarter (26%) of the fires.

Michael A. Greene and Craig Andres. 2004-2005 National Sample Survey of Unreported Residential Fires. U.S. Consumer Product Safety Commission, July 2009.

 

 

 

 

 SMOKE ALARMS IN U.S. HOME FIRES FACT SHEET

Smoke alarms provide an early warning of a fire, giving people additional escape time. In telephone surveys done for NFPA, almost all households (96%) reported having at least one smoke alarm. That still leaves roughly five million households with no smoke alarms.

Smoke alarm presence and performance in reported home fires

In 2009-2013, smoke alarms sounded in more than half (53%) of the home fires reported to U.S. fire departments.

Reported home structure fires and fire deaths by smoke alarm performance

2009-2013

Three of every five home fire deaths resulted from fires in homes with no smoke alarms (38%) or no working smoke alarms (21%).

 The death rate per 100 reported home fires was more than twice as high in homes that did not have any working smoke alarms (1.18 deaths per 100 fires), either because no smoke alarm was present or an alarm was present but did not operate), as it was in homes with working smoke alarms (0.53 per 100 fires).The death rate from reported fires in homes that had at least one smoke alarm (0.59 deaths per 100 fires) was one-third (36%) lower than in homes that had no smoke alarms at all (0.98 deaths per 100 fires).

The death rate was much higher in fires in which a smoke alarm was present but did not operate (1.89 deaths per 100 fires) than it was in home fires with no smoke alarms at all.

In reported home fires with smoke alarms:

  •  Almost half (46%) of the alarms were powered by battery only.
  •  Two-thirds (67%) of home fire deaths were caused by fires in homes with smoke alarms powered by battery only.

 

In reported home fires large enough to activate the alarm,

  •  Hardwired smoke alarms operated 94% of the time
  • Battery-powered smoke alarms operated in four out of five (80%) fires.

*Homes include one- or two-family homes, manufactured homes, as well as apartments or other multi-family housing. In general, any fire that occurs in or in a structure is considered a structure fire, even if the fire was limited to contents and the building itself was not damaged. Estimates were derived from USFA’s National Fire Incident Reporting System and NFPA’s annual fire department experience survey.

Source: Smoke Alarm in U.S. Home Fires, Marty Ahrens, September 2015 NFPA, 1 Batterymarch Park, Quincy, MA 02169, www.nfpa.org Fire Analysis & Research Division, osds@nfpa.org

 

Reasons that smoke alarms did not operate

In fires in which the smoke alarms were present but did not operate,

  •  Almost half (46%) of the smoke alarms had missing or disconnected batteries. Nuisance alarms were the leading reason for disconnected smoke alarms.
  •  Dead batteries caused one-quarter (24%) of the smoke alarm failures.
  •  Only 7% of the failures were due to hardwired power source problems, including disconnected smoke alarms, power outages, and power shut-offs.

 

Reason smoke alarm did not operate in reported home structure fires  2009-2013

  • Missing or disconnected battery (46%)
  • Dead or discharged battery (24%)
  • Unclassified reason for failure (9%)
  • Hardwired power failure, shut-off or disconnect (7%)
  • Lack of cleaning (6%)
  • Defective unit (5%)
  • Improper installation or placement (3%)

Interconnected smoke alarms, smoke alarms in the bedroom increase safety

In a Consumer Product Safety Commission (CPSC) survey of households with any fires, including fires in which the fire department was not called, interconnected smoke alarms were more likely to operate and alert occupants to a fire.1 People may know about a fire without hearing a smoke alarm.

  •  When smoke alarms (interconnected or not) were on all floors, they sounded in 37% of fires and alerted occupants in 15%.
  •  When smoke alarms were not on all floors, they sounded in only 4% of the fires and alerted occupants in only 2%.
  •  In homes that had interconnected smoke alarms, the alarms sounded in half (53%) of the fires and alerted people in one-quarter (26%) of the fires.

 

According to another CPSC study, when the door was closed, a smoke alarm sounded 10-20 decibels softer in the next room. The sound was also about 20 decibels softer on a floor above or below.2 Having smoke alarms in the bedrooms make it more likely that a sounding alarm will be loud enough to wake someone who was asleep when a fire started

 

*Homes include one- or two-family homes, manufactured homes, as well as apartments or other multi-family housing. In general, any fire that occurs in or in a structure is considered a structure fire, even if the fire was limited to contents and the building itself was not damaged. Estimates were derived from USFA’s National Fire Incident Reporting System and NFPA’s annual fire department experience survey.

 

1. Michael A. Greene and Craig Andres. 2004-2005 National Sample Survey of Unreported Residential Fires. U.S. Consumer Product Safety Commission, July 2009.  

2. Arthur Lee. The Audibility of Smoke Alarms in Residential Homes, Bethesda, MD: U.S. Consumer Product Safety Commission, September 2005, revised January 007  Source: Smoke Alarm in U.S. Home Fires, Marty Ahrens, September 2015

 

NFPA, 1 Batterymarch Park, Quincy, MA 02169, www.nfpa.org Fire Analysis & Research Division, osds@nfpa.org