Nest Protect 2nd Generation Smoke + Carbon Monoxide Alarm review

Test score

93%

Key features

  • Smoke alarm
  • Battery/Mains
  • Smart optical smoke alarm
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 verdict: The best smoke alarm you can buy

The Nest Protect 2nd Generation Smoke + Carbon Monoxide Alarm is a smart smoke alarm that’s two products in one – offering protection against CO and smoke. Launched back in 2017, it sounds as a traditional smoke alarm would do, while also sounding an alarm through your smartphone. As it doesn’t come with a heat detection function, it won’t be suitable for homes in Scotland from 2022. But does it do a good job of detecting smoke and how quickly does it sound the alarm? We tested it to find out, so read on for our full review.

Pros
  • Extremely quick to sound in all smoke tests
  • Sends alerts to your smart phone
  • A Best Buy as a CO alarm too
Cons
  • Only the price
This is a truly outstanding alarm. There aren’t too many products that are double-winning Best Buys, but this smart Nest smoke and CO alarm is one. As a smoke alarm, it was quick to sound in all four of our test fires and the quickest to sound in three.
When dealing with smoke from a flaming solvent-based fire, it was twice as quick as the slowest alarms we’ve seen. And it detected smouldering cotton smoke more than three times faster than the least responsive alarm on test. It will also sound an alarm on your smartphone when it detects smoke – simply download the free Nest app on your phone to link it up. This Nest alarm is also a really good carbon monoxide detector – in fact, it was so good that it’s one of our Best Buy carbon monoxide alarms.
So, don’t worry about this Nest alarm being a few years old now – it’s still up there with the very best products we’ve tested. But as it’s not a heat detector and can’t be linked to one, it won’t be suitable for homes in Scotland from February 2022 when the law changes.

Ei Electronics Ei141RC review

Test score

86%

Key features

  • Smoke alarm
  • Mains only
  • Ionisation smoke alarm

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 verdict: An excellent smoke alarm

The Ei Electronics EI141RC mains-powered ionisation smoke alarm is designed to last for 10 years. It comes with a standard 9V battery as a back-up power supply so it will still operate during a power cut. It detects smoke by creating an electric current inside the alarm – when smoke enters, the alarm sounds. The manufacturer advises that this type of alarm is ideal for a bedroom. By buying the Ei168RC RadioLink base, you can link the EI141RC with other connected EI alarms in your home, so that when one sounds, they all sound. This makes it suitable for Scotland when the law changes in 2022. But is it any good at raising the alarm when smoke is in the air? To find out, we tested it. Read on for our full review.

Pros
  • Fast to sound in all of the smoke tests we set it
  • Easily loud enough.
Cons
  • None that we found in our tests.
This is an excellent smoke alarm – it did a hugely impressive job of detecting smoke and raising the alarm in our tests, which is why we’re happy to make it a Best Buy. It’s also suitable for homes in Scotland when the law changes in 2022. When set to detect smoke from fast-flaming plastics fires, both alarm samples we tested did an outstanding job in sounding quickly. The same can be said for its speedy responses when set the challenge of sniffing out smoke from our liquid solvents fires, where it was incredibly quick to sound. And it was also fast at detecting smoke from test fires made of cotton and of wood. It was easily loud enough in our sound output tests.

Kidde Firex KF10 review

£13.00Typical price

Test score

79%

Key features

  • Smoke alarm
  • Mains only
  • Ionisation smoke alarm

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verdict: A great smoke alarm

The Kidde Firex KF10 is a mains-powered smoke detector with a replaceable 9V alkaline back-up battery. It uses an ionisation type smoke sensor, which the manufacturer claims is best suited for areas with a risk of fast-flaming fires. It features a tamper-resistant locking device to prevent it being removed without the appropriate tools. The KF10 is suitable for homes in Scotland, where from February 2022 smoke alarms need to be able to link to other alarms in the home. You can hardwire it to 23 other compatible mains-powered alarms, such as the Kidde KF30 heat alarm, to create an interconnected system: if one alarm activates, all the others will be triggered too.

The alarm has a six-year warranty. But is it any good at raising the alarm when needed? To find out, we tested it. Read on for our full review.
Pros
  • Fast at detecting smouldering plastic and solvents
  • Easily loud enough
Cons
  • Not as quick when reacting to cotton or wood fires
This smoke alarm did well in our tests and it’s a Best Buy. It reacted quickly to smoke from smouldering plastic and solvents and it wasn’t bad when detecting burning cotton or wood. It topped 90 decibels, which is more than loud enough. And when connected to the Kidde KF30 heat alarm, both alarms sounded in good time.

FireAngel ST-622 10 Year Thermoptek Smoke Alarm review

Test score

78%

Key features

  • Smoke alarm
  • Battery only
  • Optical smoke alarm
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 verdict: Quick to sound and affordable

The FireAngel ST-622 10 Year Thermoptek Smoke Alarm comes with a 10-year lifespan – the battery is sealed inside the alarm, so you’ll never have to replace the batteries. But it can’t be linked with other smoke and heat alarms, so it won’t be suitable for homes in Scotland when the law changes in 2022. It’s certainly affordable, but how good a job does it do at detecting smoke? We tested it back in 2017, so read on for our test results.

Pros
  • Sounded quickly in all of our test fires
  • Excellent value
Cons
  • None
This Best Buy smoke alarm from FireAngel did a good job of sounding the alarm quickly when tested with smoke from all of our test fires. But it can’t be linked with other smoke and heat alarms, so it won’t be suitable for homes in Scotland when the law changes in 2022.
When tasked with detecting smoke from a smouldering wood fire, it was the third fastest to respond and it was runner-up when dealing with smouldering cotton smoke. It represents excellent value, too, and it comes with a 10-year sealed battery. So, don’t spend any time worrying that it might be a bit long in the tooth. It might come from the class of 2017, but it’s still one of the best smoke alarms we’ve seen.

Aico EI3016 review

£46.00Typical price

Test score

72%

Key features

  • Smoke alarm
  • Mains only
  • Optical smoke alarm

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 verdict: A good smoke alarm

The Aico Ei3016 mains-powered smoke alarm is designed to last for 10 years. It has an inbuilt rechargeable lithium battery which acts as a back-up power supply, so it will still operate during a power cut. It detects smoke using an optical sensor, which the manufacturer says is best for detecting slow, smouldering fires in the home. If you buy the separate Ei3000MRF wireless module, you can link the Ei3016 with other connected EI alarms in your home, such as the Aico EI3014 heat alarm, so that when one sounds, they all sound. That means this alarm will be suitable for homes in Scotland when the smoke alarm law changes in February 2022. But is it any good at raising the alarm when smoke is in the air? To find out, we tested it. Read the full review for our verdict.

Pros
  • Fast at detecting smouldering wood or plastic
  • Easily loud enough
Cons
  • Not as quick as the best when reacting to cotton or solvent fires
This smoke alarm did well in our tests and isn’t far behind our Best Buys. Overall, we were pleased with how quickly it detected smoke and raised the alarm, but we’ve seen a handful of models that are quicker. The Aico Ei3016 was fast when reacting to smoke from smouldering wood and plastic, but not as quick at detecting burning cotton or solvents. But when tested in combination with the Aico EI3014 heat alarm, both alarms sounded in good time. In our sound tests, it was easily loud enough for all to hear.

FireAngel ST-750 10 year Thermoptek Smoke Alarm review

Test score

71%

Key features

  • Smoke alarm
  • Battery only
  • Optical smoke alarm

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 verdict: A pretty good smoke alarm

The FireAngel ST-750 10 year Thermoptek smoke alarm comes with a sealed and tamper-proof battery that will give you a decade’s worth of smoke detection. FireAngel tell us that the ST-750’s thermally enhanced optical sensor allows it to detect fires quickly. To put this to the test, we tested it at our lab. Check our verdict, fire test results and the total test score for this FireAngel smoke alarm to see whether it’s one to consider or one to be left on the shelf.

Pros
  • Not bad in all smoke tests
  • Fast when dealing with smoke from a solvents fire
Cons
  • Not as fast as our Best Buys

 

 

FireAngel SB1-R review

Test score

70%

Key features

  • Smoke alarm
  • Battery only
  • Optical smoke alarm

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 verdict: Sensitive and quick

The battery-powered FireAngel SB1-R smoke alarm uses optical or photo-electric sensors to detect large particles of smoke and raise the alarm. This means that it’s one for places like hallways, bedrooms and living rooms. As it can’t be linked to other alarms, it won’t be suitable for homes in Scotland when the alarms regulations change there in 2022. The manufacturer tells us that it’s designed to detect smoke reliably for up to 10 years, that you’ll need to replace the 9V battery every 12 months and provides it with a three-year warranty. But how well does this FireAngel smoke alarm detect smoke and is it loud enough to raise the alarm when there’s a fire? To find out, we tested it. Read on for our full review and test results.

Pros
  • Affordable
  • Quick to sound
  • Loud enough.
Cons
  • We’ve seen alarms that are a bit faster all round.
This smoke alarm did pretty well in our tests and isn’t that far away from becoming a Best Buy. But it won’t be suitable for homes in Scotland when the law changes there in 2022, as it can’t be linked to other alarms. Overall, we were pleased with how quickly it detected smoke and raised the alarm, but we’ve seen a handful of alarms that are quicker off the mark, so we can’t add this FireAngel to our Best Buy line-up.
It was fast when reacting to smoke from smouldering cottons and did a good job of detecting smoke from fast-flaming plastics, but we’ve seen alarms that are faster. It wasn’t bad when sounding the alarm in the presence of smoke from both wood and solvent fires. And in our sound tests, it was easily loud enough for all to hear.

Kidde i9080 Kidde Smoke Alarm with Emergency Escape Light review

£14.00Typical price

Test score

68%

Key features

  • Smoke alarm
  • Battery only
  • Ionisation smoke alarm
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 verdict: Inconsistent

The Kidde i9080 smoke alarm has an escape light to guide you through a smoky room, as well as a ‘hush’ feature that silences the alarm for 10 minutes if you accidentally set it off. It comes with replaceable batteries and isn’t interlinked, so it will not be suitable for homes in Scotland when the alarms law changes in 2022. The main question is how quickly and loudly does this smoke alarm respond in the event of a real fire? We put it to the test on four different types of fire to find out how quickly it triggers, how loudly it sounds and how bright the escape light actually is. Read on for our verdict, fire test results and the total test score for this Kidde smoke alarm.

Pros
  • Triggers quickly with fast flaming plastics and solvent fires
  • Easily loud enough to be heard
Cons
  • Slow to sound with our wood test fire
  • Slow when detecting smoke from our cotton test fire

 

 

FireAngel FP1640W2-R review

£80.00Typical price

Test score

68%

Key features

  • Smoke alarm

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 verdict: A reasonable smoke alarm

With the Fireangel Pro FP1640W2-R mains-powered smoke alarm you can enable text alerts or test the system using your smartphone or other portable device. It also has wi-fi connectivity, and can link wirelessly to other devices in the range, such as the FireAngel Pro FP1740W2-R heat alarm, to form an interconnected network. This means if fire is detected it one area of your house, all the alarms will sound together, making it suitable for homes in Scotland once the smoke alarm law changes in February 2022. It has an in-built lithium battery with a 10-year life that acts as a back-up power supply, so it will still operate during a power cut. It comes with a five-year guarantee. But is it any good at raising the alarm when smoke is in the air? To find out, we tested it. Read on for our full review.

Pros
  • Fast at detecting smouldering wood
  • Loud alarm
Cons
  • Not as quick as the best when reacting to plastic or cotton or solvent fires
This smoke alarm did well in our tests but doesn’t quite make the grade as a Best Buy. Overall, we were pleased with how it detected smoke, but we’ve seen models that are quicker to react. It was fast when sensing the smoke from smouldering wood, but not as quick to detect burning cotton, plastic or solvents. However, its alarm is loud and clear when it sounds and when tested in combination with the FireAngel Pro FP1740W2-R heat alarm, both reacted to the danger in good time.

Kidde 10SCO review

Test score

67%

Key features

  • Smoke alarm
  • Battery only
  • Optical smoke alarm
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 verdict: A mixed bag

The Kidde 10SCO alarm can detect smoke and carbon monoxide. It has a replaceable 9V battery that can be accessed conveniently through a hatch in the front of the alarm, and it comes with a 10-year warranty. It can’t be linked to other alarms in the home and that means it won’t be suitable for homes in Scotland after the February 2022 law change. But what is it like at detecting smoke and sounding the alarm when there’s a fire? We tested it to find out. Read on for our verdict, fire test results and the total test score for this Kidde smoke alarm.

Pros
  • Fast with smoke from a plastics fire
  • Speedy to sound with solvents and wood fires
  • Loud enough
  • Few false alarms
  • A Best Buy when tested as a CO alarm
Cons
  • Not as impressive with smoke from a cotton wool fire

 

 

First Alert SA200 Smoke Alarm review

£6.00Typical price

Test score

67%

Key features

  • Smoke alarm
  • Battery only
  • Ionisation smoke alarm
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 verdict: Affordable but imperfect

The First Alert SA200 is a basic and affordable smoke alarm, so don’t expect to find features such as a hush button or an emergency escape light on this model. To find out how quickly this First Alert alarm detects smoke, we tested it with four different types of fire. Read on to find out how well it did in our smoke alarm tests and whether the cheap price represents good value or a false economy.

Pros
  • Fast when reacting to smoke from solvent fire
  • Loud enough
Cons
  • Not very quick to sound when tested against the smoke from wood fires
  • Slow

 

 

First Alert SA700 Long Life No Nuisance Smoke Alarm review

£20.00Typical price

Test score

67%

Key features

  • Smoke alarm
  • Battery only
  • Optical smoke alarm
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 verdict: Not a bad alarm

The First Alert SA700 Long Life No Nuisance smoke alarm comes with a 10-year sealed battery, so you won’t need to replace the batteries for this alarm’s lifetime. It can’t be linked to other smoke and heat alarms, so this means that it won’t be suitable for homes in Scotland when the law changes in 2022. It comes with a ‘hush’ button to use for weekly testing, but how good is it at detecting smoke in an emergency? To find out, we tested it. Keep reading for our verdict, fire test results and the test score for this First Alert smoke alarm.

Pros
  • Fast to sound when detecting smoke from solvent fires
  • Not bad with wood fire response times
  • Loud enough
Cons
  • Not as fast to sound as our Best Buys

 

 

Ei Electronics Ei100B Smoke Alarm review

£9.00Typical price

Test score

65%

Key features

  • Smoke alarm
  • Battery only
  • Ionisation smoke alarm
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 verdict: Not consistently quick to sound

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.

Pros
  • Sounded quickly in two test fires
  • Better when reacting to smoke from fast flaming fires
Cons
  • Too slow in our wood fires test
  • Slow to sound in our cotton fire test

 

Cavius 2001-033 review

£23.00Typical price

Test score

64%

Key features

  • Smoke alarm
  • Battery only
  • Optical smoke alarm

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 verdict: Satisfactory but no better

The Cavius 2001-033 smoke alarm is tiny at just 4cm in diameter, but it’s designed to do exactly the same job as larger alarms. It’s powered by a replaceable CR2 battery, the kind you might use in a camera, and it uses photo-electric sensors to tell you when there’s smoke in your home.

It can’t be linked to other alarms, so it won’t be suitable for homes in Scotland when the law changes in February 2022. Based on the technology it uses to detect smoke, it would be best to place it in a bedroom, living room, hall or landing. It comes with a two-year warranty.
But what’s this compact smoke alarm like at detecting smoke? To find out, we tested it. Read on for our verdict and fire test results for this Cavius battery-powered smoke alarm.
Pros
  • Quick to detect and sound the alarm when sniffing out smoke from a plastics fire
  • Loud enough.
Cons
  • We’ve seen alarms that are faster to sound in our wood cotton and solvents tests.
We’ve seen many alarms that are slower to sound than this Cavius model, but we’ve also seen many faster alarms. Because of that, this alarm is quite a way away from breaking into the ranks of our Best Buy smoke alarms, and it won’t be suitable for homes in Scotland when the law changes in 2022.
Overall, its response times were pretty mixed. It was faster than many alarms to detect smoke in our flaming plastics tests, but in other smoke-detection tests it wasn’t particularly quick. However, it sounded in all eight of our tests, and was loud enough to hear, so overall we would describe this alarm as satisfactory.

Ei Electronics Ei2110e review

£49.00Typical price

Test score

63%

Key features

  • Smoke alarm
  • Battery only
  • Optical thermal smoke alarm
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 verdict: Too slow to sound with some types of fires

The Ei Electronics Ei2110e is a radio-linked smoke alarm – it can work in combination with other similar alarms in your home. This means that if one smoke alarm detects a fire, all of the other linked alarms should sound. You can buy the alarm as either battery powered or mains powered. We tested it to find out how well it can detect smoke from four different types of fire. Read on for the full results of our fire tests and our verdict on this Ei Electronics smoke alarm.

Pros
  • Quick when dealing with smoke from solvent fires
  • Not bad when responding to cotton smoke
  • Loud enough
Cons
  • Slow when dealing with smoke from wood and plastics fires
  • Dim escape light

 

 

FireAngel ST-625 Thermoptek Smoke Proof Smoke Alarm review

Test score

62%

Key features

  • Smoke alarm
  • Battery only
  • Optical smoke alarm
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 verdict: Slower than many

The FireAngel ST-625 Thermoptek Toast proof Smoke Alarm comes with a five-year warranty and – as its name suggests – claims to be ‘toast proof’. It isn’t interlinked, so it will not be suitable for homes in Scotland. To see how well this alarm detects smoke from real fires, we sent it to our lab. Read on to find out how quickly it responded to four different fires and to find out whether this Fire Angel is actually ‘toast proof’.

Pros
  • Loud enough
  • Few false alarms
Cons
  • Not fast enough at detecting smoke
  • Too slow when tested against smoke from wood fires
  • Slow with cotton fire smoke
  • Not quick enough to detect smoke from a solvents fire

 

 

Kidde 2SFW review

Test score

61%

Key features

  • Smoke alarm
  • Mains only
  • Optical smoke alarm

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 verdict: Not bad

The Kidde 2SFW mains-powered optical smoke alarm can be fitted as a standalone alarm or used as part of a wireless network of alarms. This means that it will be suitable for homes in Scotland after the alarms law changes there in 2022.

There are two buttons, one to test it – we recommend you do this weekly – and a ‘hush’ button to silence it after sounding. A 9V battery will provide back-up power if there’s a power cut. And it comes with a warranty from the manufacturer covering its six-year lifetime. But what’s it like at detecting smoke and sounding the alarm?
We tested it to find out. Read on to learn about how this Kidde mains-powered smoke alarm fared in our tough lab tests.
Pros
  • Quick to detect smoke from a plastics fire
  • Fast to sound when dealing with smoke from a solvents fire
Cons
  • Too slow with our wood based fire

 

 

First Alert SA300 Easy Hush Smoke Alarm review

Test score

61%

Key features

  • Smoke alarm
  • Battery only
  • Ionisation smoke alarm
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verdict: A curate’s egg of a smoke alarm

The First Alert SA300 Easy Hush Smoke Alarm comes with a ‘hush’ button, which allows the alarm to be silenced in the case of a false alarm. It uses replaceable batteries and isn’t interlinked, so it won’t be suitable for homes in Scotland when the law changes in 2022. To find out how sensitive it is to smoke from more than just burned toast – which you might need the hush button for – we tested it. Read on for the results of our smoke alarm tests for this First Alert alarm and find out what happened when we put it up against four different fires.

Pros
  • Fast at detecting smoke from plastics fires
  • Quick at sensing smoke from solvent fires
  • Not bad when challenged with cotton fires
Cons
  • Too slow when detecting smoke from wood fires

 

 

 

FireAngel WST-630Q review

£30.00Typical price

Test score

60%

Key features

  • Smoke alarm
  • Battery only
  • Optical smoke alarm

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verdict: We’ve seen better

The FireAngel WST-630Q smoke alarm comes with a sealed 10-year battery. This means that for the lifetime of the product, you won’t need to worry about the battery running low and having to buy another one. It comes with a five-year warranty. It’s an optical or photo-electric alarm and uses infrared light to detect smoke. The manufacturer tells us that it’s designed for living rooms, dining rooms, bedrooms, hallways and landings.

It’s part of FireAngel’s Wi-Safe range and can be linked to other alarms in your home, so that when one sounds, they all sound. But how good is it at detecting smoke? We tested it to find out. Read on for our full review of this battery-powered smoke alarm from FireAngel.
Pros
  • Fast to sound when detecting smoke from a plastics fire
  • Loud enough.
Cons
  • We’ve tested alarms that were faster to sound in our wood and cotton fire tests.
This isn’t a bad smoke alarm but we’ve tested alarms that responded more quickly in most fire situations, and that’s why we can’t make this FireAngel alarm a Best Buy. In our tests, we found that in comparison to other alarms, it detected smoke quickly when responding to our fast-flaming plastics test. And it wasn’t slow when detecting smoke in our solvents fire test. However, when working to sniff out slow-burning wood smoke, it was pretty slow, and a bit quicker when set to detect smoke from a cottons fire. But when it did sound the alarm, it was easily loud enough.

FireAngel ST-230 review

£30.00Typical price

Test scoreShow Context

57%

Key features

  • Smoke alarm

Compare

Which? verdict: Satisfactory

The Fireangel Pro ST-230 mains-powered smoke alarm is claimed to use ‘Thermoptek technology’, which combines optical sensing with thermal enhancement to speed up its reaction time. It’s mains powered but has an internal back-up battery with a 10-year life to ensure it still operates if there’s a power cut. You can hardwire it to other compatible devices in the Fireangel Pro range, such as the FireAngel Pro HT-230 heat alarm, to create an interconnected network, so that if fire is detected it one area of your house, all the alarms will sound together. This means it will be suitable for Scottish homes once the smoke alarm law changes in February 2022. It comes with a two-year guarantee. But how good is it at detecting smoke and raising the alarm when needed? Read the full review for our expert verdict.

Pros
  • Fast at detecting smouldering wood
  • Loud alarm
Cons
  • Slow at reacting to cotton or solvent fires
This smoke alarm is some way short of being a Best Buy. It was fairly quick when sensing the smoke emitted from a wood fire, and decent at alerting you to burning plastic. However, its response time was sluggish when we tested it with burning cotton or solvents. On the plus side, when its alarm sounds it’s very loud. And when tested in combination with the FireAngel Pro HT-230 heat alarm, both products sounded the alarm in good time.