Smoke Alarms

Battery-powered smoke alarms have been in the market since the 1970's।

An estimated 94% of all USA homes are equipped with at least one detector.
The NFPA (National Fire Protection Assoc.), states that one-half of the people who have died in home fires were those in the 6% that did not have alarms.
In 30% of home fires where smoke detectors were present, they did not work due to dead or missing batteries or the unit had not been properly connected.
Homes that have smoke alarms typically have a death rate that is 40-50% less than the rate of homes without alarms.
Based on the above statistics, it is evident that we should have our homes equipped with smoke alarms.
There are presently two types offered for sale in our markets, the ionization and photoelectric types.
Ionization - a small amount of radioactive material is used to ionize the air in the sensing chamber. This air becomes conductive permitting currents to flow between two charged electrodes, reducing the conductivity to a predetermined level. This sets off the alarm. The advantages of this alarm are the fast response to flaming fires and they are cost efficient. This type is the most common alarm sold.
Photoelectric - consists of a light emitting diode and a light sensitive sensor in the sensing chamber. The presence of suspended smoke in the chamber scatters the light beam. The scattered light is detected and sets off the alarm. This type responds more rapidly to slow-smoldering fires and white or gray smoke.
TIPS FOR INSTALLATION
Install at least one detector on each floor, including the basement and at sleeping area. The NFPA recommends installing smoke alarms inside the room. Smoke alarms are required in all new homes according to the NFPA 72, National fire Alarm Code.
Mount smoke alarms on ceilings or high walls. Remember-smoke rises. Ceiling mounted alarms should be at least 4 inches away from walls.
Wall mounted alarms should be at least 4 inches from the ceiling and not more than 12 inches. On vaulted ceilings, they should be mounted at the highest point of the ceiling.
Don't install smoke alarms near windows, outside doors or A/C ducts where the draft might interfere with their operation.
Don't paint smoke alarms. Paint and other decoration could keep them from working properly.
TIPS FOR MAINTENANCE
Test the alarms at least once each month. Use the test button or an approved smoke substitute. Clean the units in accordance with the Mfg.'s instructions.
Replace the batteries once a year or when the alarm "chirps," warning that the battery is low. A good rule of thumb is to change the batteries when changing your clocks from daylight savings time to standard time in the fall.
Vacuuming or dusting the alarm regularly and following the Mfg.'s instructions will help keep it working properly.
Replace the entire unit (smoke alarm) every 10 years.
Never borrow a battery from a detector for another use.
Make sure everyone can clearly hear and recognize the sound of the smoke detectors. Some studies have shown that children may not wake up to the sound of an alarm. Secure an electrician to interconnect the alarms in each room so that when one sounds, they all sound. .
NFPA recommends that people with hearing impairments should install alarms with strobe lights to warn them of a fire.
When purchasing smoke alarms, be sure that a reputable testing laboratory, such as Underwriters' Laboratory, approves them.
A qualified electrician should install alarms hard-wired to the home's electrical system.
Guard your family from being caught in an unsafe situation!
Install alarms; reduce the chance of harms!!
Excerpts; NASD-NFPA-FACT SHEETS