• The home smoke alarm is the greatest success story in fire safety in the last 50 years.
• NIST led collaborative research that resulted in new standards and enabled the widespread use of smoke alarms.
• Smoke alarms went from only token usage in the 1970s to nearly universal usage today, saving tens of thousands of people from injury or death.

In the 1960s almost no one had a home smoke alarm. In those early days, even a single device could cost hundreds of dollars. They were a new invention, untested, unregulated and largely unused.  

But research at the time showed that these new devices had the potential to save lives.

In 1969, NIST began recommending the installation of smoke alarms. The first major test of that recommendation came three years later when Hurricane Agnes destroyed thousands of houses across the Eastern Seaboard . To help with the relief effort, the Department of Housing and Urban Development (HUD) built 17,000 mobile homes. And because of NIST’s recommendation, each one of those homes had a smoke alarm.

Mobile homes were far more likely to catch fire than any other kind of residence at the time. Although there were many fires in those HUD mobile homes during the next three years, remarkably, not a single one of those fires resulted in death. It was a true breakthrough in fire safety — proof that smoke alarms work.

Encouraged by this success, NIST staff wanted to develop a standard to ensure that all smoke alarms were effective. They teamed up with Underwriters Laboratories Inc. (UL) and the smoke detector industry to test and improve prototype designs. Based on that work, the first standard for smoke alarms, UL 217, was published in 1974.  

But testing a smoke alarm in the lab is different from testing it in a real home. NIST researchers had more questions, like: How many smoke detectors do you need? And where is the best place to mount them? So they found houses that were about to be demolished in what would become Indiana Dunes National Park. NIST sponsored UL and the Illinois Institute of Technology Research Institute to experiment with smoke alarms using test fires in those real houses.

The Indiana Dunes tests led to a new standard for how to install smoke alarms, NFPA 74 (now called NFPA 72), and the data from those tests continue to be useful for fire research today.

NIST’s ongoing work on smoke alarms has made a real impact. Between 1975 and 2000, the share of homes with a smoke alarm rose from 10% to at least 92%. In that same period, fire deaths were reduced by about half. NIST experts continue to improve smoke alarms. Experiments in 2024 found that the new alarms detect fires sooner without increasing the rate of nuisance alarms.

Without the vision, persistence and technical skill of NIST staff members, smoke alarms might never have become the ubiquitous low-cost devices that have saved tens of thousands of people from injury or death.

Smoke Alarm vs. Bacon

Additional Reading:

NIST report: Detector Sensitivity and Siting Requirements for Dwellings, 1975.

NIST publication: A History of NBS/NIST Research on Fire Detectors, 2001.

UL standard: UL 217, Smoke Alarms, 2020.

NFPA code: NFPA 72, National Fire Alarm and Signaling Code, 2025.