A self-contained residential smoke alarm lasts about 12 years, but must be replaced no later than 10 years for safety. Some units now have a 10-year battery life or other features that cannot be extended, thus requiring it to be discarded and replaced at 10 years.
Usually around 10 years, but you must test your alarm regularly because different quality smoke detectors last for different amounts of time.
It's recommended that a smoke detector alarm be replaced every 8-10 years. It is also helpful to write the date of purchase on your smoke detector alarm for future reference.
many it depends
83m^2
Ideally, a smoke detector for every room should be in place.
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Smoke detectors work in several ways. A point to point smoke detector detects smoke when the beam projected by the transmitter is obscured in a measurable way and detected by the receiver. A photoelectric detector sees smoke particles inside the detection chamber of the smoke detector because light inside the chamber is scattered in a measurable way. An ionization smoke detector detects smoke because the smoke particles change the 'charge' on the detection plate inside the smoke detector.
lots and lots of lives have been saved by airbags. its indeed very cool.
Yes, this futuristic invention they call a "four wheeler" has saved many lives.
he saved many lives by yelling the regulators are coming although he was captured he still saved many lives
he saved many lives by yelling the regulators are coming although he was captured he still saved many lives
many soo yeah many were saved like BILLIONS
kW = I x E x pf/1000. Take this figure and multiply it by the amount of hours that the smoke detector is in operation. pf = power factor.
lots
3,613,435 and counting