If you live in Delhi, you must be aware that the air quality has been hazardous the past few days. You should limit your exposure to this harmful air pollution by wearing certified pollution masks when outdoors and using an effective air purifier when indoors. Here, I’ll give you the main points to keep in mind when selecting an air purifier.

Full disclosure: I run a start-up, Smart Air India, which makes and sells affordable air purifiers and pollution masks.

What Does An Air Purifier Do?

As its name suggests, it purifies unwanted particles from the air we breathe. It does this by cycling the air in a closed space through a series of filters that trap the pollution.

What To Look For

The filter: Make sure it comes with a genuine HEPA {High Efficiency Particulate Air} filter.

The Clean Air Delivery Rate {CADR}: This is like the horsepower rating of the purifier—or the tonnage rating of an air conditioner—and this is what will help you determine the right air purifier for your space.

The larger the room, higher the CADR you need. For a 300 sq-ft room, the CADR in CFM should be at least 200 {340 in CMH or m3/h}.

Replacement filters: You will have to change your HEPA filter every few months or even every few weeks in the most polluted of times, so take a look at the replacement filter cost and availability.

Pre-filter: This is a filter that goes before the HEPA filter and filters out larger particles like dust and hair so that the HEPA filter can last longer. If the pre-filter is washable, that’s better.

Activated Carbon Filter: This is optional and its purpose is to remove smells and gases, like formaldehyde. Not everyone needs a carbon filter but it’s good to have.

What To Avoid

Ionisation filters that generate ozone: Most air purifiers that have ionisers generate ozone and that is a harmful pollutant.

UV and photocatalytic filters: Again, this does more harm than good.

Recommended Air Purifiers

Here are some of the best air purifiers on the market for an average bedroom:

There are many more air purifiers out there in the market you can go for. The best is to do your own research, read independent reviews, and see the data on how effective each of these actually is before going for it.

Keep It Simple

To sum it up, pick an air purifier that has a HEPA filter and a pre-filter at the minimum, and see how easily and affordably you can get the replacement filters.

Breathe safe!

Looking for even more options? We’ve got a whole list!

Featured photo source: designmilk via Flickr[CC BY-SA 2.0]