Types Of Smoke Detectors

You did not stumble on this review perchance. The likelihood is that if you are here, you are enquiring about the types of smoke detectors out there. If you are, you are in the right place, read through this guide to find out the types of smoke detectors available.

at any time of the day or night and without a fire alarm to provide an alert, fatality can and does often occur. On average, someone in the US dies in a fire every 2.5 hours, and someone faces a fire-related injury every 30 minutes.

Many of the house fires that do occur could easily be prevented with an investment in a smoke detector. Most smoke and fire alarms are equipped with sirens that are loud enough to alert an entire household, but homeowners who have fire alarms in more than one room are more protected and more likely to avoid fatality, injury, and property damage.

Smoke detectors provide 24-hour prevention from fire damage, because of this every household and office should have at least one working smoke detector.

Without a properly installed and maintained smoke and fire alarm, any building is at risk of the destruction that fires can bring. Smoke and fire detectors are there to protect the premises by alerting the presence of the smoke that a fire emits.

In many instances, the smoke and fire alarm alerts the property in time for the fire department to arrive before any permanent damage is caused, preserving the property’s condition and averting any unnecessary financial situations.

What Is a Smoke Detector?

A smoke alarm is a device that combines smoke detection and a loud alarm together in one unit. The alarm sounds if it detects smoke in large amounts, like in a fire.

A smoke alarm, when properly installed, tested, and maintained gives you an early warning of a fire, which increases your chances of getting out.

Why Use Smoke Detectors?

Having smoke detectors placed in various locations around your home allows for fast and effective detection. The smoke detector siren will warn you, day or night, that there is a potential fire, allowing you to quickly check the nature of the problem and hopefully prevent any damage.

When placed in the right location, the smoke alarm can also help firefighters quickly locate the fire in the home, allowing them to better focus their efforts.

How do Smoke Detectors Work?

Since smoke rises, smoke detectors are always placed on the roof for ideal detection. There are two common types of smoke detectors to choose from photoelectric and ionization. Photoelectric sensors use a beam of light within the detector to sense any smoke in the air.

The beam will shoot in a straight line when the air is clear. In the presence of smoke, the light will scatter, this is when the alarm will go off. Ionization detectors, on the other hand, use a chamber with a small electrical current.

When smoke enters the chamber and the level of ions in the air changes, the electrical current drops and the alarm will sound.

Each function is beneficial in different instances and because of this, one is not necessarily better than the other. It is, however, recommended to have one of each of these functions on each floor of your home and in high-risk areas, such as the kitchen or near fireplaces and heating appliances.

What should I do if the alarm goes off?

Every household should have a fire escape plan!

  • Have a home escape plan and make sure that everyone knows what to do.
  • Practice the pre-planned fire drill at least twice a year.
  • Identify two ways to get out of every room.
  • Decide on a meeting place outside the home.

Where should smoke alarms be located?

There are two important things to remember when deciding where to put smoke alarms:

  • Most fires start in the kitchen.
  • Smoke alarms are to warn people asleep in bedrooms.

Install at least one smoke alarm on every level of your home, including the basement (but not in unfinished attics).

  • Put smoke alarms in the hallways that lead to each bedroom.
  • On floors without bedrooms, install the smoke alarm in or near each living area such as dens, living, and family rooms.
  • Put a smoke alarm on the ceiling at the bottom of any staircase leading to the upper floors.
  • Mount the smoke alarm high on walls or ceilings (remember—smoke and hot gases rise). Wall-mounted alarms should be placed at least 10 to 30 cm down from the ceiling. The ceiling-mounted alarm should be placed at least 10 cm away from the nearest wall. If ceilings are pitched, install the alarm near the ceiling’s highest point.

What type of smoke detector should you get?

All smoke and fire alarms provide protection, but the type of protection that you receive depends on the type of fire alarm that you purchase. Along with the various types of smoke and fire alarms available on the market, there are also several types of sensors available that all serve different purposes including ionic smoke detectors, photoelectric smoke alarms, and even a combination of the two.

They all serve different purposes and the type of smoke and fire alarm needed depends on the type of fire you are looking to protect against. The ionic sensor works by ionizing the air and causing a current to flow between the plates; when any type of smoke enters the chamber, it disrupts the current and the alarm will go off to inform homeowners that smoke is sensed.

The ionic sensors respond quickest to fast and quick-burning fires that can rapidly damage the property. The photoelectric sensor works by reflecting light into the chamber, opposite the sensor. If any smoke enters the chamber, it reflects the light back at the sensor, causing the alarm to sound.

The photoelectric sensor provides maximum prevention against slow-burning and smoldering fires. There is a large difference between slow-burning and quick-burning fires and since no one knows what type of fire may occur, the best protection is provided through a dual-sensor smoke detector. A dual-sensor effectively detects all fires regardless of their burn rate.

Below, we would break down all the types of smoke detectors, and what you should know about them before purchasing any:


The first smoke detector type, ionization alarms are generally more responsive to a flaming fire (for instance, when a lit candle tips over and ignites a curtain), according to the National Fire Protection Association (NFPA). These alarms use “ions,” or electrically charged particles, to help detect smoke in the air. Know this:

Ionic smoke detectors,

  • Detects fast, flaming fires.
  • Detects smoke produced by flammable liquids, loosely packed light combustibles, and kitchen grease.


The second type of smoke detector is photoelectric, which uses a light beam to help detect the presence of smoke. According to NFPA, these alarm types are more effective at sounding when a fire originates from a smoldering source, like a lit cigarette that falls into a couch cushion. Smoldering fires may fill a home with dangerous gases before a fire ever erupts. Know this:

Photoelectric smoke detectors,

  • Detects slow-burning, smoldering types of fires.
  • Detects smoke caused by cigarettes burning in furnishings and bedding.


So, which alarm to choose? While both types of smoke detectors are designed to help detect any house fire, no matter the source, each technology has its advantages and can offer an earlier warning over the other, depending on the origin of a fire.

The challenge is that it’s impossible to predict which type of fire could erupt in your home, which is why the NFPA says the best protection is offered by having both alarm technologies in your home.

There are a couple of ways to get this done.

If your existing detectors are ionization smoke alarms, you can purchase photoelectric smoke alarms and install one next to each ionization unit. If you don’t know what type you have, check your owner’s manual.

Another option: If the budget allows, consider replacing all of your existing smoke alarms with dual-sensor devices, which combine both ionization and photoelectric technologies in a single unit.

Other detectors and alarms you should also take note of:

  • Heat alarm

Heat alarms do not detect smoke at all but instead alert you to an unexpected rise in temperature. They do this by using a thermistor to measure the air temperature. Once it reaches a set limit (around 58°C), the alarm will sound.

Heat sensors are therefore ideal for kitchens because they do not give false alarms when cooking causes smoke or steam. They are also suitable for use in garages, as they won’t be triggered by exhaust fumes or dust from machinery. They should not be used in other rooms in the house, as they don’t provide the quick response that a smoke alarm will give.

  • Combined alarms or multi-sensors

A combined or multi-sensor alarm contains both optical and heat sensors, so it can detect both smoke and heat. This allows it to respond quickly to all types of fire, whether that be a slow, smoldering fire or a fast-burning blaze.

As both sensors are constantly being intelligently monitored, it is very unlikely that a false alarm will be triggered. This type of alarm is recommended for bedrooms, living rooms, dining rooms, landings, and hallways.

  • Battery alarms

Most smoke alarms are fitted with a battery, which must be replaced once a year. You should test your alarm at least once every six months by pressing the ‘test’ button to ensure that it is still in good working order. If the battery starts to run low, the alarm will alert you with an intermittent chirping noise. You should then replace the battery as soon as possible.

You can also buy sealed alarms that come with a 10-year battery, meaning that you don’t need to worry about replacing the battery throughout the alarm’s life. You will need to replace the whole unit once the battery has run down.

  • Mains alarms

Mains alarms are connected to your house’s electricity supply, so you don’t need to keep replacing the battery to maintain a good working order. They also have an inbuilt battery to ensure that they will still function in the event of a power cut.

All new buildings in the UK are required to have mains alarms fitted, as well as properties that have undergone a significant refurbishment. Because installation requires working with mains electricity, they must be installed by a qualified electrician.

  • Interconnected alarms

Interconnected alarms provide an additional level of safety by ensuring that if one alarm is triggered, all other alarms also sound. This means that no matter where you are on the property, you will be able to hear the warning. Alarms can be connected wirelessly using radio frequencies, preventing the need for complicated or disruptive cable installation.


With the above review, you should find it easy to pick a smoke detector. It has been simplified so you understand, and know which is the best for you.