Odds are if you look at the ceiling right now, you will spot some detectors on it. Similarly, if you go to your boiler cabinet (a bit difficult if you’re in an office), you should see another detector close to it, called a carbon monoxide detector. These 2 little hunks of plastic are some of the most important electrical items in your home or office, and have saved countless lives over the years. But there’s one thing we get asked a lot, which is how do these life saving devices actually work?

What Do Smoke Detectors Do?

Smoke detectors are an essential early warning system in your home or workplace. A small piece of moulded plastic protects the inner electronic device, which will sound an alarm whenever it detects traces of smoke in the air. This early warning against fires can give you and your family time to escape a blaze, or extinguish a small fire before it can get out of control. Most rooms in your house should have a smoke detector installed, but the kitchen, living room and bedrooms are especially important sports. Similarly, all workspaces should be equipped with smoke detectors in key locations to protect employees.

How Do They Work?

Generally speaking there are two types of smoke detector – photoelectric and ionization.

Photoelectric detectors:

These work by using a beam of light to detect the presence of smoke in the air. This light is projected through a small chamber, and the “eye” that can see the light is pointed towards the side of the beam. When smoke particles float into the beam, the light reflects off which sends an electronic signal to sound the alarm.

Ionization alarms:

These use tiny amounts of radioactive material (don’t worry, it’s harmless!) to ionize the air inside an electrified detection chamber within the alarm. As smoke enters the chamber, the particles interrupt the ionized electronic charge, creating a drop in voltage. When a drop is detected, a signal is sent to activate the alarm.

What Do Carbon Monoxide Detectors Do?

If smoke detectors are important, then carbon monoxide detectors are essential. Their job is to detect carbon monoxide in the air and warn you if it’s present. Carbon monoxide is a tasteless, odourless, colourless gas that can leak into your home from your heating and plumbing systems. Carbon monoxide is an incredibly dangerous gas – when you breathe it in it displaces the oxygen in your blood, depriving your heart, brain and other vital organs of blood. Large amounts of carbon monoxide can overwhelm you within minutes and cause you to lose consciousness and suffocate. In smaller amounts, it can cause carbon monoxide poisoning, which is equally harmful and can cause long term health problems and even death.

How Do They Work?

Your carbon monoxide detector is designed to pick up on carbon monoxide in the air and alert you to its presence, allowing you to get out of the house and get the problem fixed safely. Carbon monoxide detectors come in three basic kinds: biometric, metal oxide semiconductor and electrochemical.

Biometric detectors:

These feature a small chamber filled with a chemical gel that mimics carbon monoxide’s effects on blood. When the gel comes into contact with carbon monoxide particles, it changes colour. That colour change is detected by an electronic sensor that triggers the alarm.

A metal oxide semiconductor detector:

These contain a small silica chip, and this is what interacts with carbon monoxide in the atmosphere. This interaction causes a drop in the current flowing through the chip, similar to the way ionization smoke detectors work. When the voltage drops, the alarm sounds.

The most sensitive carbon monoxide sensors use electrochemical sensors made of electrodes submerged in chemical baths. These are less commonly used for households safety, but will often be found in industrial settings.

At HR Hislop, we believe that safety is everything. That’s why we are always happy to help you choose, install and test smoke and carbon monoxide alarms in your home or office. No job is too small for us, and we want you to ensure you feel safe in your home, without the constant worry of smoke or carbon monoxide. If you would like to know more about smoke detectors and carbon monoxide detectors, or you have any questions about how they work, just get in touch with us today.