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Smoke alarm and battery function 42 months after installation: a randomized trial
Corinne Peek-Asa1, Jingzhen Yang, Cara Hamann
1Injury Prevention Research Center, University of Iowa, Iowa City, Iowa 52241, USA. corinne-peek-asa@uiowa.edu
American Journal of Preventive Medicine
|September 15, 2010
Summary
Photoelectric smoke alarms with lithium batteries offer the best long-term function compared to ionizing alarms with zinc batteries. This extended functionality may justify their higher initial cost for reliable home safety.
Area of Science:
- Fire safety engineering
- Consumer product reliability
Background:
- Presents findings from the longest follow-up study on smoke alarm and battery performance.
- Evaluates the long-term functionality of smoke alarm and battery combinations.
Purpose of the Study:
- To examine differences in the long-term function of various smoke alarm and battery types.
- To identify which combinations provide the most reliable performance over time.
Main Methods:
- Randomized trial involving 691 households.
- Allocated participants into ionizing/photoelectric smoke alarm and zinc/lithium battery groups.
- Measured smoke alarm function in 633 households after 42 months.
Main Results:
- Overall, 81.9% of smoke alarms were functional after 3.5 years.
- Photoelectric alarms with lithium batteries were 2.9 times more likely to function than the least reliable combination (ionizing with zinc).
- Alarm functionality correlated with nuisance alarm frequency, higher in ionizing alarms.
Conclusions:
- Photoelectric smoke alarms and lithium batteries demonstrate superior long-term functionality.
- These combinations may be a worthwhile investment for sustained safety despite higher costs.
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