If you are living in an Indian city, you are probably exposed to very high levels of air pollution every day. Data released by the World Health Organization (WHO) report for May on global pollution states, “According to the latest urban air quality database, 98% of cities in low and middle income countries with more than 100,000 inhabitants do not meet WHO air quality guidelines.”
But while people understand how harmful the air outside is, most don’t realize how deadly indoor pollutants are.
Pollutants and allergens such as residues, fungal spores, indoor smoke, paint fumes, varnishes, pet dander, etc., are now causing what is known as the Sick Building Syndrome. For while your house may look clean, it may still have a very high concentration of pollutants. Couple that with the air outside that streams in regularly, and what you’ve got is a deadly cocktail.
In February, another report from the WHO suggested that more than 50% of the deaths due to pneumonia among children under the age of 5 are caused by particulate matter inhaled from household air pollution. And as many as 3.8 million premature deaths annually from non-communicable diseases—strokes, ischaemic heart disease, chronic obstructive pulmonary disease (COPD) and lung cancer among them—are in some way attributable to the exposure to air pollution inside homes.
Indoor air purifiers can help considerably in such a scenario.
How does an air purifier work?
The idea is very simple. An indoor air purifier sucks in the air present in the room and runs it through multiple layers of filters to capture the impurities and particulate matter, which would include pollutants, allergens and other viruses. Depending on how fine the sieves are, a majority of air-purifier filters can catch airborne particles larger than 0.3 microns—microns being the standard unit for measuring air particles. Each micron is 1/25,400 of an inch.
What to look for while buying a purifier
You need to have a general idea about the room size where you’ll use it. A lot of manufacturers claim very high clean air delivery rates (CADRs), but there really is no industry standard. However, if you have a very small-sized purifier claiming a CADR rate comparable to those which are double in size, that should perhaps raise a red flag—the laws of physics don’t change, and a purifier needs to be able to draw in and throw out large amounts of air to fulfil the CADR promise. All purifiers are also sold with a general rating about their coverage area according to room size, and that should give you a better idea of what will fit better in your home.
Second, the quality of the filter is something you should keep an eye out for. A thicker filter with greater density will be better able to capture finer airborne particles than one which is not as well-made. Also, if you have two options—one purifier with one or two filter layers, and one that offers even more layers, follow the simple rule of “more is better”.
The design of the purifier, in terms of the air-inlet vents and outlet, also matters. The ones which have the air-outlet vent at the top, allowing for quicker dispersion around the room, are better. If they throw out clean air from the sides, there’s a chance that the flow across the room will be impeded by furniture, etc.
Position for maximum effectiveness
Where you keep the air purifier in the room will have a bearing on how effective it is. First, it should not be squeezed between walls or furniture. You need maximum airflow. Second, conventional wisdom suggests that we should place these purifiers on the ground, but that is not always true. If your purifier has inlets close to the ground, we would suggest keeping it on top of something—otherwise it will start sucking in the dust from the floor like a vacuum cleaner, clogging up the filters sooner.
Maintenance tips for your air purifier
Manufacturers do not offer specific guidelines on maintenance. But here are some tips:
No indoor air purifier will be able to work efficiently if the filter is clogged with dust. You can use a vacuum cleaner or a blower to clean these filters. The frequency of this cleaning will depend on how dusty your home is.
The dust and air-quality factors will decide how often you need to replace the purifier filter. Most purifiers will give you a notification when it is time to change the filter.
The cost of replacement filters varies across brands and devices. For example, the Xiaomi filter costs Rs2,499 while the Philips HEPA filters cost around Rs3,000. Blueair’s higher-quality filters cost around Rs6,000.
Make room for clean air
These are the best air purifiers, in terms of performance and features, for different room sizes
<20 SQ.M ROOM
This range would cover most bedrooms, study and reading rooms or children’s rooms in modern homes, and larger bedrooms and halls that are around 200 sq. ft in size.
Xiaomi Mi Air Purifier 2 (Rs9,999*)
It has a compact design, with air- intake vents on all sides; the filter is circular in design. You can control this with your smartphone through the Mi Home app (free on Android and iOS)—the purifier’s biggest attraction, and perhaps also its biggest shortcoming for users who aren’t too tech-savvy. Rated at 310 m3/h CADR.
Philips 2000 Series (Rs22,995 (AC2887)
The AC2887 purifier has a multilayer filter set-up. Its sensor, AeraSense, detects the pollutant and particulate level in the room and alters the settings accordingly. The 333 m3/h CADR rating is enough for bigger rooms as well. It also displays the room’s air-quality parameters.
<30 SQ.M ROOM
If you have a big hall, such as a dining room plus living room combination, you need a powerful purifier that can cover around 300 sq. ft
Blue Pure 211 by Blueair (Rs22,990)
The clever design immediately stands out—the entire top part is the fan, while the bottom section is a replaceable filter, with a pre-filter fabric wrapped around it. This fabric is available in multiple colour options. The Blue Pure 211 is assisted by a very high 590 m3/h CADR rating, which is among the highest in this price range.
Panasonic F-PXM55a (Rs34,995)
This purifier deploys high-efficiency composite and deodorizing filters, and uses the nanoe technology—a nanoe is a fine (5-20nm) acidic water particle with an electric charge; these wrap the anti-microbial hydroxyl particles and remove hydrogen from viruses, allergens, bacteria, etc.
>30 SQ.M ROOM
These work best for larger-size rooms or specific activities—for example, home gyms and home theatre areas that require finer cleaning
Honeywell Air Touch S (Rs39,990)
Honeywell uses a HiSiv filter with a unique honeycomb design and is one of the few purifiers that uses a HEPA Grade11 filter and offers 300 m3/h CADR. It can also be controlled from the Hplus app (free on Android and iOS). It looks gorgeous too.
Atlanta Healthcare Gama 501(Rs32,200)
The Gama 501 uses a seven-stage filtration process to clean the room’s air, and has a CADR of 365 m3/h. It also has a UV lamp which kills the very fine micro-organisms as well as bacteria and viruses that may have gotten through the filters, sterilizing the air. The design is all about minimalism.
Philips 3000 Series (Rs32,995)
The thick filter, called NanoProtect HEPA, with a separate allergen-removal mode, makes the AC3256 extremely efficient. Philips has retained the LED light ring on the purifier which provides an indication of the room’s air quality. It has a high CADR of 367 m3/h, and the touch controls are really cool.
*Prices may vary.