Carbon Monoxide Detector Placement

Where should Carbon Monoxide Detectors be placed?

Don’t panic.

We’re going to explain the best (and worst) locations and why it’s important. It could keep your family safe.

A build-up of carbon monoxide (CO) can occur quickly if an appliance such as a boiler develops a problem.

Ensuring your property has at least one detector fitted will alert you to these dangers.

where to install a carbon monoxide alarm

Depending on the type of alarm you’ve chosen, it’s worth noting that it will contain some sort of audible sound or light alerting you to the positive detection of CO.

Did you know, there are on 430 deaths each year in the United States from carbon monoxide poisoning.

Top Questions:

What rooms can I install a detector in?
Should I install more than one alarm?
What types of alarm are there?
Where is the best placement of a CO detector?
What alarms can you recommend?

How does a carbon monoxide detector work?

An alarm will contain a sensor (sometimes more than one) that detects the amount of CO in the air around it which is why the correct placement is important.

how does a carbon monoxide detector work.

If it picks up a high reading, the alarm will sound. Modern CO detectors may contain a digital display that can store readings over a certain length of time, usually until the unit is reset.

This is particularly helpful if a slow leak is occurring in your home.

Should I install more than one alarm?

This is actually a very appropriate question.

Dependent on your property size, a single detector should be OK, otherwise for a 3-bedroom house, we suggest 2 to 3 alarms be fitted.

The reasons for this are:

  1. The location of fuel burning sources in your home such as boilers, gas stoves, heaters and motor vehicles.
  2. You probably have more than one floor or even an attached garage.

If you own a mobile home or caravan, we would strongly recommend installing a carbon monoxide detector there as well.

It’s safer to have all bases covered when deciding how many to fit in your property.

What rooms should I install a carbon monoxide detector?

So far, you’ve learnt how a CO detector works and a rough idea on the area’s of your home most at risk to possible exposure.

This infographic (see below) provides you with a checklist of the best and worst places for installation.

what rooms to install carbon monoxide alarms

To recap, you should NEVER install a detector right next to a fuel source (as mentioned above) or in a bathroom.

The alarm could malfunction or provide inaccurate readings due to heat or steam.

A bit more detail about the worst placement areas:

  • Lofts and cellars – you may not be able to hear the alarm going off
  • Near air vents or extractor fans where a higher level of oxygen is present
  • By windows or door for the same reason above
  • Obstructive places such as next to furniture
  • In any enclosed spaces like cupboards
  • Very hot or cold rooms (-5C or above 40C)
  • Areas where dust or dirt could block sensors

Where is the ideal Carbon Monoxide Detector Placement?

The number one place to install your alarm would be next to any sleeping areas such as a bedroom.

This is so you can hear it.

Ideally, if you have a landing or hallway near these areas, this would be a perfect spot.

Other notable places may include:

  • the kitchen, but not directly next to your cooker, oven or any fans
  • In a garage. Likely spaces where you keep your car or storage of any fuel appliances
  • Near a gas boiler – not right next to it though!

What about actual placement of a CO detector?

To recap, you know how many alarms you need, the best locations and where not to install a detector.

Your probably familiar with smoke alarms? They are usually installed on ceilings, or up high on walls because heat and smoke rises.

Carbon monoxide is slightly lighter than air so fitting one directly to your ceiling is bad.It also mixes with air, so can easily get trapped around the home.

placement of a carbon monoxide detector

There are two recommended ‘zones’ for placement of your detector.

If you decide to install an alarm on your wall, make sure it is at least 150mm away from the ceiling, but 300mm is an ideal drop. Keep it above window or door height too.

Some detectors feature a digital display. These types are best situated at eye level.

So, if you’re installing more than one, maybe mix up the placement.

This video below contains useful information on installing your detector.


How to install a CO detector

This really depends on the type of detector really.why is my detector going off.

Plug-in carbon monoxide detectors are just that. If your mains sockets are too low (although that’s fine) an extension lead cable will allow you to position your alarm where you need it.

Buying an alarm that has some sort of battery back-up is better in case of a power outage.

Some modern alarms contain a lithium battery situated inside the unit. These are long-life types of detector, usually lasting from 5 to 10 years.

Cheaper detectors use standard batteries for their power. Just remember to check and replace these regularly.

The final type, and popular with businesses and factories, are hard-wired alarms. Installation is a bit more tricky, and again, ensure a back-up power option is available.

Just make sure your read all the instructions that came with your new alarm regarding fitting, turning the detector on and how to dispose of properly.

Alarms on sale to the general public tend to be either battery operated or powered by an AC adapter.

Over the years, as technology has improved, battery powered type detectors offer a timescale of around 6 to 10 years. Others may be rechargeable once AC power is connected giving extended use.

Similar to smoke alarms, the majority offer some sort of ‘TEST’ button which ensures the device is working and reading levels of CO correctly.

Correct carbon monoxide detector placement is important. Your chosen detector must be fitted close to your ceiling, but not on the ceiling as CO has a similar density to air.

It’s worth noting that regulations insist on alarms be installed within close proximity to sleeping areas, so you may need to install more than one detector.

What types of Carbon Monoxide Detectors are available?

There are many types of carbon monoxide detectors available on the market right now. We dissect the many options to make it easy when your deciding which one to choose.

In the US, CO detectors are regulated by the Underwriters Laboratories who provide safety consulting and certification for products. All detectors that bare the trademark ‘UL’ symbol are deemed safe and thoroughly tested by UL.

types of carbon monoxide alarms

Nowadays, in certain states, alarms must be fitted to all new build properties.

Detectors are designed to measure levels over time of carbon monoxide that may be present in the surrounding environment by using either an LED or audible system, preferably both. This is to provide an adequate warning to evacuate the premises.

Unlike smoke alarms, CO detectors are not designed for detecting smoke (although dual CO/smoke alarms are available to buy).

Newer models now offer a warning or ‘chirp’ when battery levels are low.

Carbon Monoxide Sensors

Many years ago, first generation detectors offered a pad which would change color (black or brownish if I recall) if CO was present. A lot of improvements have been made since then.

Instead of just a visual warning, modern detectors may now offer an audible sound, digital displays that show readings or even color coded LED light systems.

Depending on levels of CO that detectors have picked up on, the alarm may change tone to indicate a low, medium or high level detection. This is particularly useful if a slow leak has occurred.

There are four types of sensor that vary in cost, speed and accuracy.

Opto-chemical detectors use a pad that changes color upon reaction with carbon monoxide. This shows very little warning, are often cheap but I suppose is better than no detector at all.

Bio-mimetic sensors act like hemoglobin’s (protein found in red blood cells) which darkens when CO is present. This can either be seen directly or connected to an infra-red sensor within the alarm. Battery lifespan is around 2 to 3 years although a lithium battery may prolong this.

This type of detector is popular with businesses such as hotels and hospitals where other products (such as disinfectants) may prompt another type of alarm to give a false reading.

Sensors containing some sort of Electro-chemical is a fuel cell that has been adapted not to produce power but provide a current or signal that can target gas (i.e. Carbon Monoxide) very precisely in the atmosphere.

It can measure CO concentration levels very effectively and accurately, making it a hugely popular type of alarm. So much so, that it dominates the market n the US.

The fact it uses minimal power is a bonus and so some alarms on the market offer a 10 year lifetime guarantee.

The final type of carbon monoxide sensor is by way of a semi conductor integrated and monitored by a circuit board. Thin wires are heated to a high temperature to operate correctly. The way this works is oxygen increases resistance whereby CO reduces it. A sensor monitors these levels.

These type of detector have a lifespan of around 5 to 10 years, but requires a large amount of power so you’ll probably discover that these versions tend to be hard-wired into the mains.

Electro-chemical detectors are starting to displace these type of alarms., although they remain popular in Japan.

Digital Carbon Monoxide Detectors

The majority of detectors use an audible system as a primary warning signal, but recently digital detectors offer the user readings to make things easier.

Functions include current and peak levels (from memory) measure over a period of time.

Readings taken from a digital display are useful to assist engineers or emergency services about the amount of CO in the atmosphere so relevant action can be taken.

Portable Carbon Monoxide Detectors

These types are usually reserved for professionals who carry them to observe or detect carbon monoxide. These offer real time measurements and are particularly useful for property managers, engineers and maintenance personnel.

Wireless CO Detectors

Although quite new, wireless detectors are great for connecting alarms together to, say, via a central LED panel system.

They are also a great solution to those with visual or hearing impediments or heavy sleepers. They can give a warning to somebody by connection to a pillow or pad for example.