Ionization Smoke Alarms

Ionization smoke alarms are very common in the US. It's likely that the current smoke alarms in your house fall in to this category. These type of alarms rely on a tiny amount of a radioactive substance called Americium 241 to help detect smoke particles in the air (see the infographic below for details).

Ionization smoke alarms are best at detecting a flaming type of fire. They do not work as well as detecting a smoldering fire in the house. An ionization smoke alarm does provide a warning for fires it can detect it may not be the best choice to cover all potential types of house fires. A better option is a dual function smoke alarm - one that has both ionization and photoelectric sensors. Look for a post next week that explores photoelectric type alarms.

How an Ionization Smoke Alarm works. Infographic courtesy of the National Fire Protection Association.