Home Fire Alarms and Smoke Alarms Should be an Essential Part of your Home Security Strategy

Home Fire Alarms or Home Smoke Alarms are a way to alert you of smoke within your house. This early detection will allow you and your family to get out of the house safely before the fire progresses.

home fire alarms

Smoke detectors are an essential part of any home security strategy. Even if you do not have the other home security devices installed in the house, you should install smoke detectors first.

Smoke detectors have two parts: one to detect the smoke and the second to set off the alarm to alert people of the smoke. Home smoke alarms run off of 9-V batteries or a 120-V house current.

How Home Smoke Detectors Work

The two main types of detectors are Photoelectric detectors and Ionization detectors.

Photoelectric detectors

A photoelectric detector has a light source which emits white light or a low-level laser and a sensor that can 'see' the light. The sensor is placed within the chamber at a 90 degrees angle from the light source. When smoke enters the chamber it deflects the lights and the sensor picks up the light. This triggers the alarm or horn to go off.

Photoelectric detectors are better at detecting smoky or smoldering fires, such as from a mattress.

Ionization detectors

An ionization detector has a very small amount of radioactive material (americium - 241 to be scientific) between two electrically charged plates. The amount of radiation is extremely small. The radiation is alpha radiation which cannot even penetrate a sheet of paper, and is blocked by several centimeters of air. The only potential danger is if you inhale the material. So, don't inhale close to the ionization chamber.

The radiation causes an ionized current to flow between the two plates. When smoke enters the chamber, the current flow is disrupted and this triggers the detector to set off the alarm.

Ionization detectors are better at detecting the smaller amounts of smoke from a flaming fire. They are also fairly common because they are inexpensive.

Installation and Maintenance Tips

You should place the detectors high on the walls or on the ceiling because smoke rises. You should keep the detectors away from windows and doors where air drafts can interfere with the purpose of the alarm.

You should install detectors on every level of you house. For new houses, there are regulations that a smoke detector should be in each sleeping room and must be interconnected.

You can purchase smoke detectors that run off the electrical wires in your house. Or you can purchase detectors that run off 9-V batteries.

Also, do not paint over the smoke detectors. This could interfere with the operation of the detector by blocking potential smoke from entering the chamber.

Hard-Wired Detectors

If you have home fire alarms that run off your electrical wires you should have a professional install the system. An advantage of hard-wired alarms is that when one alarm goes off, all of the alarms will sound. This helps alert people earlier if they have a big house and cannot hear an alarm from another part of the house. These detectors should have a back-up 9-V battery source in case your power goes out.

Battery Smoke Detectors

Installing home fire alarms that runs off of 9-V batteries is a very easy installation. Even if you have two left thumbs you will be able to install it. The detectors have instructions on them, but you are just securing the detector to the wall or ceiling using screws. Some detectors even have double-sided tape to secure the detector to the wall.



You need to check each battery and smoke alarm on a monthly basis. The batteries should be replaced at least once a year.

Another helpful way to help remind you is to change your batteries when you change your clocks. You would be changing your batteries twice a year, but is better than forgetting to replace and the home fire alarms not working.

The whole detector should be replaced every ten years.


Because photoelectric detectors and ionization detectors excel in detecting different types of fires, you should have both types of detectors within your house. There are some units that have both types of technology within them.

To get more great safety and maintenance tips on home fire alarms, you can go to the National Fire Proteciton website.

Once you have the detectors in place, you should go through a home escape plan with each member of the family. That way everyone will know what they should do in case of emergency.

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