Ei Electronics Ei100B Smoke Alarm review
Test scoreShow Context
- Smoke alarm
- Battery only
- Ionisation smoke alarm

The Ei Electronics Ei100B smoke alarm comes at an attractive price and is backed with a five-year warranty. But there’s no escape light on this model, and it won't be suitable for homes in Scotland when the smoke alarms law changes in 2022. To find out how quickly this alarm responds to smoke, we tested it. Our verdict on how well this alarm detects smoke is based on how it responded in the presence of smoke from four different test fires. Read on for the results of our tough tests and our verdict on this EI Electronics smoke alarm.
What's included:- Pros and cons
Last checked by Which?
December 2021
First reviewed by Which?
July 2013

Technical specifications
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
- 41%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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