FireAngel ST-620 Thermoptek 10 Year Life Smoke Alarm review
Test scoreShow Context

- Smoke alarm
- Battery only
- Optical thermal smoke alarm
FireAngel has labelled the ST-620 smoke alarm ‘toast-proof’, due to its efforts to avoid nuisance false alarms. But has it got what it takes to react quickly and effectively to a real house fire? To find out, we put it to the test against four different types of fire and assessed both its response times and volume. Read on for our results, which reveal whether the ST-620 smoke alarm is one you can rely on.
- Pros and cons

Technical specifications
Test results
The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.
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- 0%Lowest score
- 43%Average score
- 93%Highest score
Put us to the test
Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.
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