Fire Safety Learning Center

Articles and other information related to fire safety equipment and procedures in Illinois.

SMOKE DETECTORS – DON’T SET THEM AND FORGET THEM

According to the National Fire Protection Association (NFPA) and the United States Fire Administration (USFA), the presence of smoke detectors in residential structures rose from less than 10% in 1975 to more than 95% in 2000, which coincided with a 50% reduction in the number of home fire deaths over that period of time. The number of homes with smoke detectors has remained consistent since then, with surveys consistently reporting that 95% or more of households report having at least one smoke alarm. Such percentages will no doubt continue, as Illinois, like many states, requires that newly constructed multi-unit dwellings have interconnected, hardwired smoke detectors.

While outreach was needed in decades past to educate people about the importance of smoke detectors, today they have become so prevalent that they are nearly an afterthought. The assumption is that nearly every building has them, and people assume that if they are present they are functional.

Such assumptions, however, are potentially dangerous, as residential structures are the leading property type for financial loss, fire injuries, and fire deaths.

A closer look at the numbers behind the presence of smoke detectors, how smoke detectors are used and maintained, and the characteristics of modern fires, reveals the continuing importance of outreach emphasizing the important, lifesaving role of smoke detectors and, more specifically, the importance of properly maintaining smoke detectors.

Perhaps most importantly, the need for early warning of a potential fire hazard is greater than ever: the time needed to escape a fire in a residential buildings is more than 5 times shorter than it used to be and as short as 3 minutes, due in large part to faster developing fires attributable to modern materials and building layouts.

Next, the prevalence of smoke detectors is likely overstated because most studies rely on telephone surveys and self-reporting.  As a result, according to the U.S. Consumer Product Safety Commission's National Smoke Detector Project, which performed home inspections of the general population to determine whether smoke detectors were present, most studies overestimate the percentage of residential structures with smoke detectors by approximately 10%.

While it is likely that only around 75% of all residential buildings actually have at least one working smoke detector, the situation may be worse for condo buildings. According to the United States Fire Administration: nearly 2/3 of multifamily residential buildings that suffered the type of fire most likely to cause injury or death did not have a smoke detector present.

Compounding the problem are the number of residential smoke detectors that are inoperable. Multiple studies have found that the smoke detectors that people believe to be operable often are not. This is perhaps due to people incorrectly approaching smoke detectors as they do Ron Popeil’s famous rotisserie – they “set it and forget it,” assuming that a smoke detector, once installed, will last for its designated 7-10 year life.

For example, one randomized controlled trial examining battery operated smoke detectors found that only 15 months after installation, 50% of the detectors were inoperable. Similarly, a study of smoke detectors powered by lithium batteries, typically assumed to last 10 years, found that nearly half were not working in year 4 and nearly 75% were no longer operable in year 6.

Similarly, a study by the Centers for Disease Control and Prevention (CDC) determined that nearly half of typical 10-year smoke detectors powered by lithium batteries were inoperable due to a dead battery in their last 3 years.

The consequences of not having a working smoke detector can be severe, regardless of whether smoke detectors are not present or are present but inoperable:

  • Approximately 60% of home fire deaths resulted from fires with no working smoke alarms.
  • The death rate for reported home fires was more than twice as high in residential structures without a working smoke detector.
  • The death rate for reported home fires is higher when a smoke detector is present but does not operate than when there is no smoke detector at all.

It’s important to note that these risks are even more dire at night and in the winter:

  • From 2012-2014, there were more than twice as many fatalities between 11:00 p.m. and 6:00 a.m. as there were during either daytime hours or evening hours.
  • Fatal fires are nearly twice as likely in winter months versus summer months.

Fortunately, appropriate testing and servicing of smoke detectors makes a tremendous difference. 90% of smoke detector failures are attributable to neglect: missing or dead batteries, a disconnected power source (battery or electrical), lack of cleaning, and improper installation or placement.  All of these causes of smoke detector failures can be remedied by proper installation and regular maintenance.

Sources Cited

Performance of Home Smoke Alarms, National Institute of Standards and Technology, February 2008.
Smoke Alarms in U.S. Home Fires Fact Sheet, National Fire Prevention Association (covering the years 2009-2013).
NFPA 101 Life Safety Code, 2000 edition, National Fire Prevention Association.
U.S. Fire Statistics, Fire Loss in the United States (2004-2013), Fire Death and Injury Rates (2004-2013), United States Fire Administration.
Analysis of Changing Residential Fire Dynamics, Underwriters Laboratories.
Smoke Alarms in U.S. Home Fires, National Fire Prevention Association, September 2015.
Smoke Alarms in U.S. Home Fires Fact Sheet, National Fire Prevention Association, September 2015.
Home Structure Fires, National Fire Prevention Association, September 2015.
Civilian Fire Fatalities in Residential Buildings, Total Fire Series, Vol 17, Issue 4, July 2016, United States Fire Administration.
Requirements for carbon monoxide detectors in Chic...
Fire Prevention Tips
TOP