An air-quality sensor?

What is it?

Air-quality sensors (like Airthing’s Wave Mini, pictured) increasingly feature in home devices and detect potentially harmful substances in the air. These so-called ‘Volatile organic compounds’ (VOCS) include the smelly chemicals released by fresh paint, new furniture and cosmetics, and can also be released by open fires. ‘Particulates’ are fine solids or droplets, including smoke. These could cause allergy-like symptoms, irritation, nausea, tiredness or long-term damage to the lungs and other organs. Many devices also measure temperature and humidity, and some detect carbon monoxide, carbon dioxide and radon.

What does it do?

Usually you’ll just get charts and notifications in an app, so you can open your windows or try to find the cause. If you have a device that can exchange air-quality data with a platform such as Google Home, Apple Homekit or IFTTT, you may be able to program other devices to respond. More simply, the Awair Glow C sensor can turn a socket on or off, so, for example, you could power up a dehumidifier when humidity gets high. It costs $89 (about £83), but isn’t yet sold in the UK.

What’s the catch?

Experts point out that cheap sensors may offer poor accuracy. That might not seem important if you’re just interested in looking out for high readings or sudden changes, but you’d probably prefer a dedicated, certified product to detect carbon monoxide, for example, which can be fatal. As for VOCS, your nose may work just as well as a guide.

So can I do without it?

Take readings with a pinch of salt, but it’s an area of home automation to keep an eye on.