The Two Types of Smoke Alarms, Explained

– by Stevens & Day

Did you know that there are two different types of smoke alarms? If not, you are not alone.

Most people assume that they are protected if they have any standard smoke alarm (and a carbon monoxide detector), but that assumption may be wrong. Unfortunately, the smoke alarm industry has done a poor job of warning the public about the differences between the two technologies and, more importantly, the need to have both types in your home to adequately protect yourself and your family.

Our office recently filed suit in a case involving two people who died in a house fire, and this information might have saved their lives. Here’s what you need to know:

Smoke alarms are not created equally.

The two types of alarms on the market today use very different technologies to detect the presence of fire. ABC’s 20/20 ran a story on television years ago trying to warn the public about the differences, and you can watch that segment here:

Ionization alarms are designed to detect fast flaming fires.

These are the least expensive alarms, and it has been reported that 93% of homes in the United States use them. In the case of the suit we mentioned about, the house was equipped with several ionization smoke alarms. Unfortunately, none of the alarms sounded in time for the occupants to escape.

Photoelectric alarms are designed to detect smoky, smoldering fires.

Industry executives have acknowledged that photoelectric alarms can sound 15 minutes earlier than ionization alarms. Those 15 minutes can make the difference between life and death.

Dual sensor alarms use ionization AND photoelectric technologies to detect both types of fires.

Smoke alarm ratings

The December 2018 edition of Consumer Reports discusses the two different technologies, warns that you need both to be fully protected, and rates different smoke alarm models. Consumer Reports rated the First Alert 7010B as the top photoelectric model, the Kidde KN-COSM-1B as the top Ionization model, and the First Alert 3120B as the top dual sensor alarm. The cost of these alarms ranges from $25 to $40.

How to stay safe

In Maine, the winter season is upon us. We are firing up our wood stoves and hanging lights for the holidays. If you haven’t yet, now is an ideal time to inspect your smoke alarms to ensure that you have both types and that they are working properly. Your life, and the life of your family members, could depend on it.

If you or a loved one are seriously injured or killed as a result of a fire and want to discuss the possibility of pursuing a legal claim, or if you are an attorney looking to refer a personal injury or wrongful death case to someone with experience, please feel free to contact Dan Stevens at or 207-430-3288.

Contact Stevens & Day, LLP

82 Winthrop St.,

Augusta, ME 04330