Properly functioning smoke alarms provide an early warning of smoke and fire. They may be the only things standing between safe escape and being overcome by deadly gases. A smoke alarm becomes your "Nose at Night." Most fatal fires occur during the night when people are sleeping. The smoke and poisonous gases emitted from a fire are deadly and people may be suffocated from the gases without being awakened or even realizing there is a fire.
Type of Smoke Alarms
An ionization smoke alarm monitors "ions," which are electrically charged particles. The alarm sounds when the charge in electrical balance reaches a preset level.
The photoelectric smoke alarm uses a beam of light and a light sensor. The alarm sounds when the smoke density reaches a preset level.