What is the purpose of a smoke detector?
The smoke alarm is perhaps the most important part of any fire alarm system. In many states, law requires that all residences be equipped with smoke alarms, and for good reason: smoke detectors save lives. Widely considered by experts to be the best way to prevent fatalities in the event of a fire, a smoke detector is the central device for most fire detection systems.
A smoke detector’s purpose is a rather simple one: detecting smoke. The old adage, “where there’s smoke, there’s fire” should be taken literally when it comes to the safety of occupants. A device designed around being able to detect smoke quickly and sound off an alarm to inform the occupants to evacuate. According to the National Fire Prevention Association, 50% of all fatal home fires occur while residents are sleeping. A few seconds can make all the difference in a fire, changing what could be a fatality to a simple evacuation. A loud alarm going off when smoke is detected gives all the information needed to these residents: the alarm lets everyone know that the building must be evacuated; in addition it will startle sleeping residents awake.
How does a smoke detector work?
In short, smoke detectors notice fires by sensing smoke particles in the air, which in turn sets off the alarm, either built into the detector or connected to a central fire alarm system. The method that detectors use in detecting smoke particles differ, but hope to achieve the same goal. There are two major technologies used for smoke alarms: ionization and photoelectric.
Ionization smoke detectors have a small amount of radioactive material between two plates. These plates, when electrically charged, ionize the air, causing a current to flow between them. When smoke enters the chamber, however, the flow of ions is disrupted. This disruption in turn activates the alarm. Ionization detectors are best at responding to flaming fires.
Photoelectric smoke alarms contain a light source aimed into a sensing chamber at an angle away from the sensor. When smoke is to enter the chamber, light is reflected onto the light sensor. When this sensor detects that light, the alarm is then triggered. Photoelectric smoke detectors are best at responding to fires that have a long period of smoldering.
It is recommended by the NFPA that both technologies be used in homes. Fatal fires can be smoldering or flaming in equal measure, and as it is impossible to predict which type of fire may strike, it’s best to ensure that the smoke alarm technologies in your house can respond to both quickly and efficiently.
How do you properly place a smoke detector during install?
Having a smoke detector isn’t enough if it is placed in such a way that it cannot function properly or to its fullest abilities. Learning where to place smoke detectors throughout the home is the most important step during installation. A smoke alarm should be installed inside every bedroom, outside every sleeping area, and on every level of the home, including the attic. Fire can break out on any floor of the home, so keeping alarms on every level will maximize your perimeter of fire safety. The same goes for sleeping areas – if a fire breaks out while somebody is sleeping, having alarms near every bedroom and sleeping area will wake them up quickly so they can evacuate.
Smoke detectors should additionally be placed in living rooms, near stairways to upper levels, and in the basement. Basement smoke detectors should be installed on the ceiling at the bottom of the stairs leading upstairs. Keep fire alarms at least 10 feet away from cooking appliances in the kitchen to minimize false alarms while cooking, while still being able to monitor for kitchen fires. Do not install smoke alarms near windows, doors, or ducts, as the draft can interfere with them. Due to smoke rising, all smoke alarms should be mounted on the ceiling, or failing that, high up on the wall toward the ceiling. Rooms with pitched ceilings should be mounted on the wall, within three feet of the peak.
Why you should include a smoke detector in your fire alarm system
It’s not just good sense to keep a residence or business guarded from fire with smoke detectors – in many states, it’s the law. But law or not, having a smoke detector is an altogether good thing, good for protecting your property and the occupants within. In the scope of a greater fire alarm system, smoke detectors exist as the first line of defense in a fire. Smoke inhalation is the main cause of physical harm in a fire. Staying aware and ahead of this danger is exactly what a smoke detector is meant to do. When working in tandem with a heat detector, every type of fire, from low to high energy fires will be noticed quickly, and for everything else, the manual pull station can be a massive assistance. When installed as part of a larger fire alarm system, the smoke detector can be programmed to set off every alarm in the property, not just the built in alarm many smoke alarms come with. This functionality can be used in home smoke detectors as well, as wired or smart technology enabled smoke detectors can be connected to trigger all alarms at once. This will help further alert and inform occupants of the dangers present, giving everyone the chance to evacuate as quickly as possible.
Avoid painting your smoke alarm – paint, stickers, and decorations can interrupt the smoke alarm, causing it to work improperly, potentially risking lives. A noticeable smoke detector is a very good thing – hiding it does nobody any good. Speak with an expert if you need all of your alarms interconnected with one another – they’ll be able to help out with the wiring, if necessary, and can point you to smoke detectors that work together. Smoke detectors made by different manufacturers may not work together in this way. Every floor of your home needs a smoke detector, as well as your garage, basement, furnace rooms, laundry rooms, and any other utility spaces. Smoke alarms are an essential part of every fire alarm system, and should be among the first things installed on a property intended for residential or business use.