Smoke detectors, also known as smoke alarms, have been responsible for the prevention of untold numbers of fire deaths since the first single-station, battery-operated ionization units began being marketed to the general public starting in 1970. The early warning they provide has also been instrumental in saving billions of dollars in potential fire-related property losses. According to the US NFPA (National Fire Protection Association), nearly two thirds of all residential fire-related deaths occur in homes that either have no smoke detectors installed or in which the existing detectors were not working properly when the fire broke out. Statistics also show that, between 2007 and 2011, smoke detectors are believed to have alerted in about 50 percent of the fires occurring in U.S. homes that were reported to fire departments.
Proper Location and Installation of Residential Smoke Detectors
While having just one single smoke alarm installed in a home is better than none, proper coverage includes more than this. According to current requirements of NFPA 72, the U.S. National Fire Alarm and Signaling code, homes should have a smoke alarm installed in each sleeping room, one outside every sleeping area and, in multi-storey homes, a minimum of one on each level, including basements. Ceiling-mounted detectors should be as close to the centre of the area they’re protecting as possible. If mounted on a wall, a detector should be at least 6″ (15 cm) below ceiling level but not more than 19″ (30 cm) from the ceiling. In a room with an A-frame type ceiling, the detector should be near the peak but at least 4″ (10 cm) below the apex but not greater than 36″ (90 cm) lower. Here are some other factors to consider:
- Only use smoke alarms approved by a recognized testing agency.
- Don’t install detectors near windows, doors, air ducts or anywhere else drafts would impede their proper functioning. Keep detectors at least two-feet (60 cm) from any room corners.
- Don’t paint a detector or apply any stickers or other decorations.
- Detectors located in basements or other levels without bedrooms should be installed on the ceiling at the bottom of the stairs going to the next level.
- Don’t install detectors within 10-feet of cooking appliances. This will minimize false alarms. Also, keep alarms at least 60 to 90 cm (2 to 3 feet) from light fixtures.
- Avoid installing detectors in areas where temperatures may exceed 48°C (119°F) or drop below 5°C (41°F). This typically includes attics and garages.
- Don’t recess detectors into a ceiling or wall.
If hard-wired alarms are installed, only those with a battery backup should be used. They should be installed by a licensed, qualified electrician and should not share an electrical circuit but have their own dedicated circuit at the main electrical panel. Your detectors’ proper operation should be checked after installation.
Smoke Detector Care and Maintenance
Smoke detectors should be tested monthly, cleaned every six months and have their batteries replaced annually. If the low-battery signal (chirping sound) becomes audible, the batteries should be replaced immediately. Check detectors after returning from vacation. It’s best to have a monthly routine for alarm testing so it won’t be forgotten. This could be the first or last day of the month, payday, or whatever day seems best. Write it down on the calendar to make certain it’s not overlooked.
Testing involves two steps: pressing the test button to ensure power is available and that the horn operates and using smoke (or artificial smoke) to ensure the smoke sensor is working. Most detectors require complete replacement every 10 years. Consult your owner’s manual.