What should you look for in a smoke or carbon monoxide (CO) alarm? While features can vary, there are a few essentials every alarm should include.
1. Third-party certification
Look for alarms that have been independently tested and certified to meet current industry standards. Marks like Underwriters Laboratory (UL) Seal, ETL Listed Mark, or Canadian Standards Association (CSA) Mark indicate that the product has been evaluated against established performance criteria by a recognized third party – not just the manufacturer. UL develops safety standards and conducts rigorous testing on products to help verify they perform reliably under real-world conditions.
In Canada, consumers can also look for recognized certification marks such as ULC, cUL, CSA, or cETL, when purchasing smoke or CO alarms. These marks indicate the products have been tested and evaluated to applicable Canadian safety and performance standards.
Choosing an alarm with a recognized certification mark can help provide added confidence that it has been backed by rigorous testing, quality controls, and independent oversight before the product reaches consumers. First Alert has also been recognized as America’s most trusted fire safety brand for six consecutive years, reflecting continued consumer confidence in the brand.
| U.S. UL Mark | U.S. ETL Mark | Canada UL Mark | Canada ETL Mark | CSA Mark |
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2. Accurate detection technology
Whether it’s a smoke alarm, a CO alarm, or a combo alarm, your alarm should be designed to accurately detect potential hazards and respond within required timeframes based on industry standards. As a result of shifting home design and construction trends – modern homes are being built more open, and filled with lighter, synthetic materials – building safety requirements are shifting.
For CO alarms, performance requirements are defined by established UL 2034 standards in the U.S. and Canada, which outline how alarms must respond to different carbon monoxide concentration levels over time.
The U.S. Consumer Product Safety Commission (CPSC) worked closely with UL Solutions to help develop the UL 2034 safety standard for CO alarms in the U.S. and Canada. This standard establishes specific alarm-response requirements designed to help ensure alarms activate within appropriate timeframes based on CO concentration levels.
Under UL 2034:
- If the alarm is exposed to 400 ppm of CO, activation is required between 4 and 15 minutes.
- If the alarm is exposed to 150 ppm of CO, activation is required between 10 and 50 minutes.
- If the alarm is exposed to 70 ppm of CO, activation is required between 60 and 240 minutes.
3. Clear, actionable alerts
Alarms should provide clear, recognizable alerts – whether through loud tones, voice alerts, or visual indicators – so you can quickly understand the type of danger and take appropriate action. Some alarms may also offer features like interconnectivity or battery backup, which can provide added convenience and coverage depending on your home.
For more detailed information on testing standards and thresholds, refer to guidance from UL Solutions, Intertek, UL Solutions Canada or Intertek Canada directly.