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best smoke detectors

The 10 Best Smoke Detectors in 2021

Author: Joanna Davis

Home & Kitchen Expert

Smoke detectors can save lives in an emergency. Even with new buildings and renovations, consumers have to equip living spaces with fire detectors. A warning device should be located in the bedroom, in the children’s room and in the hallways. Ideally, the fire alarm sits in the middle of the room in a horizontal position on the ceiling. But how do I install a smoke detector? How long do the batteries last? And who maintains the smoke detector and what are the associated costs?

The following guide answers common questions about smoke detectors and provides practical tips on how to increase security in your own four walls. Before doing this, we take a look at 10 models of smoke detectors. In an FAQ area, you can find out everything important about the products.

1. First Alert Smoke Detector and Carbon Monoxide Detector Alarm

No products found.

2. Kidde 21026043

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3. X-Sense Smoke Detector

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4. First Alert BRK9120b6CP Hardwired Smoke Detector

No products found.

5. ARDWOLF Photoelectric Smoke Alarm

No products found.

6. First Alert Battery Powered Smoke Alarm SA303CN3

No products found.

7. Google S3000BWES Nest Protect Alarm-Smoke Carbon Monoxide Detector

No products found.

8. First Alert 1044091 P1010 Smoke Alarm

No products found.

9. Arikon Smoke Detector

No products found.

10. First Alert SCO7CN Smoke Alarm

No products found.

Frequently Asked Questions: Smoke Detectors

What is a smoke detector?

Smoke detectors are also known colloquially as smoke alarms or fire alarms. A smoke detector or fire alarm device emits an acoustic warning signal when there is a certain amount of smoke and a fire in apartments and rooms. This ensures an important alarm function that can save lives in an emergency. Smoke detectors can not only be used in apartments, but have also been used in a variety of other areas in recent years:

  • In transport
  • In authorities and public institutions
  • In industrial plants and commercial plants


Smoke detectors are small, rounded and usually made of plastic. They can be attached to the ceiling. Smoke detectors are often equipped with a small LED light and a test switch. With this light, users can check whether the smoke detector is ready for use or the battery is nearing its end.

When it comes to smoke detectors, we differentiate between stand-alone smoke alarms and smoke alarms with a radio module. The stand-alone smoke alarm devices work alone, while the wireless smoke alarm devices respond to connected wireless smoke alarms in the event of a fire in the house or apartment, so that all wireless alarm devices emit a signal tone. Some smoke detectors are linked to a fire alarm system so that the signal is passed on to the fire brigade.

In contrast to conventional smoke detectors, fire detectors automatically trigger an alarm. But there are also fire alarms that can be operated manually. In contrast to safe smoke detectors, the fire brigade is informed of the fire in this way. It goes without saying that the use of an automatic smoke detector is safer and therefore recommended.

How do smoke detectors work?

When it comes to smoke detectors, consumers can choose from many different techniques and types in the market. We differentiate between all smoke detector types in three categories:

  • Optical or photoelectric smoke detectors
  • Ionization smoke detector
  • Combination detector


The latter combine the detectors for heat and smoke and detectors for carbon monoxide and smoke. These combination devices usually offer a very high level of security.

How does a photoelectric smoke detector work?

In order to be able to recognize smoke formation in the room and to be able to emit an alarm signal, smoke detectors use various physical properties that indicate fire smoke. The most common types are optical or photoelectric smoke alarms, some of which are also referred to as photo-optical smoke alarms. You rely on the scattered light method. Clear air that is free from smoke reflects almost no light. But if there are smoke particles in the air, the scattered light properties of the air change.

For this purpose, the smoke detector sends out a testing light beam, which is usually generated by an infrared LED. If the light beam is scattered, this can be detected by a light-sensitive sensor on the smoke detector. This is usually located inside the device and is not visible from the outside. As soon as the sensor is triggered, the smoke detector will hit. This type of smoke detector is useful if cold smoke is to be expected at first – this is often the case with smoldering fires, for example.

How does an ionization smoke detector work?

A radioactive emitter is used with this type of smoke detector. For this reason, ionization smoke detectors manage to detect even the particles that are practically invisible and hardly reflect a beam of light, if at all. Normally, these smoke alarm devices use a radioactive substance to ensure that electricity flows between two metal plates. Because these plates are charged, they exert an electrostatic attraction on smoke particles.

If there are smoke particles in the air between the two metal plates, the air cannot conduct the flow between the plates as well. The result: The current flow is reduced, whereupon the ionization smoke detector emits a loud alarm. Although these fire alarms do their job well, they are only used sporadically. This is due to their radioactivity.

Radioactivity from ionization smoke detectors: If a fire breaks out in an apartment, which also affects the smoke detectors installed there, radioactive material can escape. For safety reasons, this means that the radioactively contaminated fire debris has to be disposed of as hazardous waste. This means considerable additional costs for the fire service.

Which is better: photoelectric or ionization smoke detector?

Ionization smoke detectors are increasingly used in the Anglo-American region. This is because people in this part of the world do not have to dispose of this type of smoke alarm as hazardous waste, but can simply throw it in with their regular household waste. In theory, however, ionization smoke detectors are more effective in fires with small smoke particles. In the case of flaming fires, these detectors strike more quickly, while optical smoke detectors can prove themselves in smoldering fires.

For this reason, the conclusion to the above question is: Both types complement each other well. When it comes to protection against possible false alarms, neither model does better than the other. Both types can be mistakenly triggered by kitchen fumes, water vapors, or more rarely, the smoke of a cigarette. From a statistical point of view, smoldering fires occur more often in bedrooms and children’s rooms, which is why consumers should prefer optical smoke alarms in these areas.

In addition to the types of smoke detectors, there are also types that are used less often, but whose functionality we would like to briefly mention at this point:

Linear smoke detector: This special model consists of a transmitter and a receiver unit. Between the transmitter and the receiver there is an infrared beam, which is reminiscent of a kind of light barrier. If the beam is weakened by the smoke, the smoke alarm device switches on. Since consumers have to install two units instead of a single smoke detector with these models, they are irrelevant for private use.

Thermal smoke alarms: These fire alarms are also known as heat alarms. They react to changes in temperature, with a further distinction being made between thermal differential detectors and thermal maximum detectors. The maximum thermal detectors trigger the alarm when the maximum temperature is exceeded. The temperature is usually around 60 degrees Celsius. The thermal differential detectors recognize when the temperature rises rapidly and trigger the alarm. These smoke alarms work with a reference thermistor and a measuring thermistor to detect the difference between the temperatures. Both thermal fire detectors have the advantage that they work independently of dust or steam. For this reason, the smoke alarms are suitable for bathrooms, kitchens or workshops.

Vibration and light smoke detectors: Not everyone can hear the high-pitched signal tone of a smoke detector. Deaf people and people with a hearing impairment use a special smoke detector that is equipped with a flash, more precisely a stroboscopic flash. Alternatively, the alarm activates a special vibration pad to indicate the danger. The good news is that it is often possible for the health insurance company to cover the costs if consumers can prove a corresponding impairment.

Which is the best smoke detector?

A general answer to this question is difficult, as it depends on the requirements of those interested in the smoke detector. While consumer A is looking for an optical smoke detector, the neighbor wants to purchase an ionization smoke detector for his company. It is therefore important that consumers are clear about their requirements for the model before buying a smoke alarm. You can then take a look at the product descriptions above and crown the personal test winner.

How does smoking affect the smoke alarm?

In most cases, smokers’ fears are unfounded. If consumers do not blow the cigarette smoke directly into the detector, nothing usually happens. This means that the risk of false positives is low.

What is a smoke detector with Wireless Networking?

In radio networked smoke alarms, there is usually an optical smoke alarm device that the manufacturer has equipped with additional radio technology. This is ideal for spacious living spaces that consumers cannot cover with a single model. Such smoke detectors can be purchased as a set because they communicate with each other in an apartment or house thanks to wireless detector technology. If one of the smoke detectors sounds the alarm, the other networked detectors also trigger.

This is useful, for example, when a resident’s bedroom is upstairs but the fire breaks out in the basement. In view of the great distance between the source of the fire and the place where the fire is located, without radio it would be possible that the residents would not notice the fire for a long time. That is a great danger to life and limb.

So that the individual smoke detectors can communicate with each other, the distances between the devices must not be too great. In addition, there must be no large or too many obstacles in the way. Consumers should therefore check to what extent this is the case and, if necessary, get a repeater so that the radio signal reaches all corners of the living space.

Smoke detector with WiFi

In addition to wireless networking, there are some smoke detectors on the market that work with a WiFi. As a rule, these models are photoelectric smoke detectors, which can often be integrated into an existing smart home system. A functioning WiFi connection is essential for the commissioning of these smoke alarms. In addition, interference with WiFi reception can disrupt the connection between the individual smoke alarms.

However, WiFi has the advantage that consumers can use an app to monitor whether, for example, the battery in the smoke detector is still working or when they should next service the smoke detector. Consumers can usually be informed about a very low battery level or other acute problems via a push notification on their smartphone. The app also shows users the alarm from the fire alarm when they are not at home. There is still the option of calling the neighbors or alerting the fire brigade.

Advantages & disadvantages of smoke alarm devices


  • Fast reaction
  • Inexpensive to buy
  • Reliable function
  • Easy to assemble
  • Powered by batteries



  • Many smoke alarms are not suitable for the kitchen and bathroom
  • Dust or smoke generation causes problems
  • Short service life depending on the battery

Comparison: batteries in smoke detectors

Most smoke alarms on the market have a lithium-ion battery built in that lasts for 10 years. It is known by many manufacturers as the “10-year battery”. With a little research, consumers can also find inexpensive models that use a 9-volt block or several AAA batteries. Smoke alarms with alkaline batteries usually last less than 3 years and are more prone to false alarms due to their weak energy cell.

The sensors of the smoke alarms with weak batteries are usually not worse. They are simply more maintenance-intensive, but usually a bit cheaper. For this reason, consumers can find models with replaceable batteries in the market even from reputable manufacturers. To make it easier for buyers to choose between the different types of batteries, we would like to briefly introduce the respective types and their properties:

  • Lithium Battery – More expensive to buy than other batteries – Significantly longer service life of up to 10 years
  • Alkaline battery – cheap to buy – Short service life of just under 3 years


When buying a smoke detector, consumers should think about which batteries they want to use. Not all devices can be operated with lithium and alkaline batteries. In order to be able to cover the energy requirements of the smoke detector, experts and manufacturers recommend using lithium batteries with a shelf life of 10 years. After this time, the products usually have to be disposed of.

Buying smoke detectors - this must be taken into account

Before consumers decide on one or more smoke alarms, they should ask themselves how many floors and rooms they want to equip with the monitors. If the smoke detector is used over several floors of the apartment, buying wireless smoke detectors makes sense. They offer comprehensive protection. Photoelectric smoke detectors are used in bedrooms, children’s rooms, basements or corridors. For bathrooms and kitchens, prospective buyers should buy fire detectors that can handle steam and heat.

Regardless of which device buyers ultimately choose – a brand and price comparison is always an option. The list of criteria and safety-relevant features is long for smoke alarms. The most important aspects that consumers should pay attention to when buying a smoke alarm device are summarized in this list:

  • Functional principle: Usually optical smoke detectors
  • Type and weight: For example a smoke alarm for a deaf person
  • Design and color: Mostly white, so that the smoke alarm on the ceiling is not too noticeable
  • Dimensions: Often between 10 and 19 centimeters in diameter and between 5 and 10 centimeters in height
  • Battery type and service life of the rechargeable battery: Ideally up to 10 years
  • Type of assembly: mostly screwed, partially glued
  • Smoke detection area and alarm volume: important in large corridors and stairwells
  • Test button and mute function: important in the event of a false alarm or battery change

The weight of a smoke alarm only matters if consumers are interested in adhesive mounting. Smoke alarms are so light that the ceiling can support the weight without any problems. A function display can also be desirable, as this allows users to ensure that the model is working as intended by looking at the corresponding LED light. Another useful feature is a dimming function that switches on automatically within a certain period of time.

Testing and maintenance of the smoke detector

Tests should be carried out once a year according to the manufacturer’s instructions. For this it is necessary to document the time of the test and to record when users change the batteries and dust them off.

Owners should follow the manufacturer’s specifications. In the operating instructions, buyers will find the individual steps to be taken for maintenance.

  • Test button: almost all certified smoke alarms have a test button located in the middle. Consumers can touch this button with a broomstick or wand, or they can press the button with their finger. A tone should then sound after a few moments. If there is no signal, there is almost certainly a defect.
  • Environment test: There should be no obstacles around the smoke detector within half a meter. In this way the smoke from the fire can rise unhindered. Consumers should ensure that neither furniture nor decorations obstruct the way to the fire alarm.
  • General test: Consumers should take a look at the entry openings through which dust and smoke can get inside. The covers should not be damaged, nor should excessive dust or insect debris clog the inlet openings. Dirty smoke alarms should be carefully dusted.
  • Use of the room: Users should check in which room they need a smoke detector. The neuralgic points include the rooms in which people sleep. The majority are still caught in a fire at night. In the respective state building regulations, consumers will find specific regulations regarding retrofitting in living spaces.
  • Battery change: With the exception of long-term batteries, in which the smoke detector is replaced, there are monitors that are operated with normal rechargeable batteries and batteries. These need to be exchanged regularly.
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Last product update on 2022-09-29 | Source: Amazon Affiliate