Every year at CES you are guaranteed to see the latest TVs and gadgets for your home. The 2017 edition was no exception, with the expected emphasis on virtual reality, high dynamic range displays, and voice controlled assistants.

But walking through the exhibition you could also notice there were a significant number of products around air quality. This theme started a few years ago and now makes a regular appearance at CES. From startups to established brands, more and more companies are now using technology to monitor or control air quality.

What technology is driving this trend? Most of these products include one or two environmental sensors that measure the concentration of some of the most common pollutants such as carbon monoxide, volatile organic compounds (VOC) or particulate matter (PM). As sensors become more power efficient and more affordable, they start to appear in consumer electronics.

The products shown at CES can generally be categorized as:

Connected monitor for smart home

Indoor air purifier

Mobile phone app or accessory

Portable or wearable pollution monitor

Within the next two years these four categories of consumer product will represent over 50% of the shipment for environmental gas sensors, according to our recent analysis

Below is a selection of 10 products I saw at CES 2017.