The recent curtain of smog smothering Beijing (aka the airpocalypse) has been Beijing’s worst on record, and that probably means you’re thinking about the air purifier you have or are considering getting. Air purifiers are a big investment, and it’s easy to be skeptical about the results you’re getting when you can’t actually see them, or when you’re getting a sales pitch. I have a lot of experience working with and answering questions about air purifiers*, so here’s the straight talk on air purifiers.
Does my air purifier really do anything?
Yes, it does. But only if you use it properly, and most people don’t. There are plenty of homes, businesses, and schools that physically have air purifiers, but the machines are never turned on. Likewise, many people turn on the machines, but only run them on the lowest speeds because they find the noise distracting. This is almost as ineffective; keeping the machine on the lowest setting is simply not enough when the AQI crawls above about 150 (this isn’t a scientific number, this is my personal threshold. Yours may vary).
My advice: learn to deal with the noise and crank up the air purifiers as high as they’ll go when the AQI gets high. For the rest of the time, find a middle setting that isn’t as loud as the highest setting, and run it on that speed. It will be much more effective that the lowest setting.
I don’t have an air purifier, but I’m considering it. What sort of investment am I looking at here?
It depends on the brand. Some machines sold in supermarkets or electronics are less than RMB 2,000. If cost is really a huge issue, something is better than nothing, but I think in that case you’re better off buying a specialty brand (IQ Air, Blue Air, or Alen) secondhand.
If you’re looking at buying new from one of those big three brands, your cost will be considerably higher. What you need depends on how many rooms you have and how big they are. If you have a standard two-bedroom, one living room apartment, you probably need three machines. If you’re looking at Alen Air, Blue Air or IQ Air, you’re looking at anywhere between RMB 13,000 at the low end all the way to closer to RMB 40,000 at the top.
Keep in mind, everything is negotiable. You can haggle for a discount, and sometimes if you get together a group of friends to buy a lot of machines, you can get a bigger discount than you would alone.
I want someone to come over and do an air test. What are they going to do?
The big three all offer free home air assessment tests. They’ll come to your home at the appointed time, and they’ll usually bring a demo model and a particle scanner. They’ll test your air with no air purifier. Then they’ll plug in the demo, show you how to work the model, and wait around 10 minutes. Next they’ll tell you how many machines they think you need, then show you that the air particles have decreased – usually, particles will have decreased by about half. If you buy, you can sometimes talk them in to coming back to your house a month, or even a year, later to test the efficacy of the machines you actually have.
My bedroom is only 15 square meters. So a purifier that covers 15 square meters is all I need, right?
Not necessarily. The fine print on those measurements is that those purifiers cover up to 15 square meters. That means they may cover 15 square meters only on the highest setting. When it’s on lower settings, it won’t cover the whole room effectively. Err on the side of caution and get a machine that covers more area.
My machine tells me to change the filter after two or three months, but the company says it needs to be changed every six months. My purifier must be wrong, right?
No. Most purifiers say the filters need to be changed every six months, and that’s true in a place that doesn’t see such constant high levels of pollution. The six month rule is even true in Shanghai. The reality is that filters fill up way faster in Beijing, and that means they need to be changed more frequently. While changing the filters is a hassle and a considerable expense, it’s the only way to make sure your air is clean, and also the best way to avoid creating motor problems in your machine. If you’re unsure, call whoever you bought your machine from and ask about it.
Isn’t the air much better inside than outside?
Probably not. From my experience testing with particle scanners in rooms without air purifiers, the pollution inside is half what it is outside if you’re lucky – I’ve been in apartments, schools, and offices where the AQI is higher inside than it is outside.
How often should I turn on my air purifier?
Always. Unless it’s a legitimate blue sky day (I personally judge by what I can see around the window), keep your air purifiers running. The more expensive purifiers shouldn’t have a significant impact on your energy bill.
Can I open the windows?
If you open your windows, turn off the purifier. Running the purifier with the windows is absolutely useless.
But it’s stuffy inside.
Yes, it is. The grim reality is that you have to choose between a hot, stuffy room with clean air, or a cooler, more aerated room with pollution. Open your windows on blue sky days, but when it’s hazy like today and this past weekend, keep those windows closed.
What if my machine breaks down?
Policies differ at each company regarding repair costs and procedures. It also depends on if you bought it from a reseller or if you bought it straight from a company. The first step is always to contact the company you bought the machine from. If you bought directly from a company, they’ll usually give you the rundown on their procedures. If you bought from a reseller, all bets are off on the responses you get. If they’re giving you the runaround, call the company that makes the air purifier. You may not fall under the warranty, but they should still be able to fix your machine.
Speaking of the warranty, how long is the warranty?
Again, this differs from company to company. Call the company you bought your purifier from, or ask before you buy. When they tell you the length of time on the warranty, ask what it’s contingent on. It may be contingent on your regularly replacing the filters. If so, it’s also probably contingent on you buying those replacement filters directly from them, and not from a third-party source.
What about buying secondhand?
Personally, I think buying secondhand is a great way to go. Air purifiers aren’t cheap, and buying secondhand is an excellent way to get a discount. Check out the classifieds section here and on The Beijinger. Yahoo! Groups like Beijing Exchange and Beijing Mamas get a lot of posts from people selling their machines.
Before you buy the machine, listen to it in person. Make sure there’s no rattling and that all the settings work. One thing to keep in mind is that buying secondhand will almost certainly void the warranty on the machine. You can still get it fixed by the manufacturer, but you’ll have to pay for it.
Have some more questions about air purifiers? Leave it in the comments section!
* I worked for Alen Air Purifiers for about a year
Photo courtesy of flickr user Kevin Dooley
