Ozone and PM2.5 data in Beijing?
Monday, 11 August 2008, Written by Julien   
I blogged yesterday about how international pressure helps Beijing improving its air. Today I found this announcement : Beijing might start to monitor ozone and very fine particle matters (PM2.5) starting from next year.

Ozone is harmful for our health but there is no data available now. Having a daily monitoring of ozone would help people avoiding pollution peaks. It would also encourage Beijing municipality to take measures against ozone pollution.

Having PM2.5 data would also be interesting as particle matters are the main pollutants in Beijing. PM2.5 concentration is important as those fine particles are the most harmful for human health. Knowing both PM2.5 and PM10 concentrations would give us a more precise overview of the situation.

Let's hope Beijing officials will not forget this promise after August 24th!
Zac wrote : lol
does beljing have bad air
fireworks wrote : Strange: my post was erased
Doesn't it sound strange to anybody to read only supporting posts in this blog? Mine was harmful to the mask business I guess. Indeed ozone nor very fine particles are removed by such masks. Have a look to the specs (especially the particle size below which particles are not trapped). At the end of the day, such masks remain useful to warm up your nose in the wintertime. But not a lot more, really.
Julien wrote : re fireworks: Check before!
Hi Fireworks, I guess you should check twice before writing. First, your comment was never erased and it is still here (see below) .
At that time, I answered your email and gave you the reference of one of the scientific articles we use. I also invited you to give us the information we would not have.
Moreover, I would appreciate if you could write in a polite manner, giving scientific information to explain the facts you bring forward.
Link to your earlier post
fireworks wrote : deeper
Hope you like debating coz your answer is not satisfactory yet: the paper you mention to answer my comment about ozone does not provide any ozone DATA, just model simulations. Here's a nice website with absolute data of PM10, NO2, SO2, CO and... ozone for BJ and other Chinese cities: www.amfic.eu Have a look and tell if the ozone 8h-average data are REALLY so bad compared to the EU standard of 120ug/m3? Doesn't look it's the case. Regarding the particle size toxicity, several articles showed that PM0.1 are the most dangerous for health (see articles from C. Sioutas, or from F. Marano). How fine are the particles trapped in your masks?
Julien wrote : re
Hi fireworks,
First, thanks for this website! It is a nice resource.
Regarding ozone, I checked the 8h average data for July 2008 on this website (we agree that ozone comparison only make sense during hot months, right), 15 days out of 31 where clearly above the 120µg/m3 threshold with at least 7 days higher than 200µg/m3. I is really bad compared with Paris (in 2007, only 3 times the peak value exceeded 180 (while below 210)!
For particles, I sure agree that the smallest particles are the most harmful, but it is still better for your health to reduce the amount of particles entering your lungs (ie smaller than 10 micrometer). Respro filters (except City) are meet the performance requirement of European FFP1 standard. Which means that they filter at least 80% of the particles with a mean diameter of 0.6 micrometer.
A few particles still come in, but the levels obtained are much less harmful for the health!
ME wrote : Masks
OK its just not normal to wear masks in life and if the air quality is that bad then leave. The point is, how much is that life style or money worth when you talk about your own health. You won't wear a mask inside but if you leave the windows open particles will still come in. I have decided to leave China and not return. I find this country is in a mad race to make money and destroy itself in the process. At least as foreigners we have the option to leave. Health is not worth risking, at all.
fireworks wrote : too small to be filtered
Hi Julian,
first, since no ozone DATA are actually provided by www.amfic.com (only modeling outputs) let's be rigourous and wait for next summer to get daily reports with real measurements. alternatively, we could look for published results from the scientific campaigns run by Chinese institutes last summer.

second, you just cannot say "A few particles still come in, but the levels obtained are much less harmful for the health!", for two reasons:
1. there are an awful lot of fine and ultrafine particles below 0.6 micrometer that therefore enter our respiratory tract even if we wear a mask (see a typical number size distribution here: http://www.particleandfibretoxicology.com/content/figures/1743-8977-5-3-1-l.jpg). Draw a line at 0.6um, and integrate both sides. you'll realize that Respro masks just filter few % (the least toxic) of the total number of particles in the atmosphere;
2. these smallest particles stay longer in our resp. tract and have been shown responsible for in...
fireworks wrote : to be continued
2. these smallest particles stay longer in our resp. tract and have been shown responsible for inflammatory effects but also mitogene effects (cancers) in the long term. Here, it's important to understand that it's not the MASS concentration of fine and ultrafine particles which matters, but their NUMBER concentration.

To finish off, I recommand to all of those who are concerned with their health to have a read thru this article from DR. WILL CHICKERING living in BJ for years, with children: www.greendragonfilm.com/documents/GDarticleinUrbane.pdf. he gives several interesting tips, and sometimes briefly states informative points like "Some masks can block larger particles, thus reducing respiratory irritation. But do not expect a mask to protect you from traffic emissions."

The majority of particles are just too small to be filtered. Your business runs on a biased information.
paul tergeist wrote :
while I agree that fireworks is right, even a less than perfect mask is better than nothing, so why not go for a cheapest solution like the masks from totobobo.com ?
Julien wrote : re
Paul, it's good to compare the solutions. First, totobobo are not so cheap now that their promotion phase is ending! Secondly, I would say Respro Techno masks are more efficient, as they also filter chemical pollutants with the active charcoal part They are also more comfortable, especially because of the velcro and the exhaust valves.
You should see both to better understand the differences!
I repost a link sent in one of the comments recently for an independent comparison: http://tiny.cc/PaDqy
TK wrote :
Interesting debate & very relevant to those of us living here. Recently I've been researching heavily into air purification in Beijing. Recently I was able to make an informed decision on a good quality air purifier and am now looking into masks. I'd like to hear your response on the following:
Yes, we know RESPRO & other non-industrial type of particulate filters don't get the smallest traces that are most dangerous. So is a bit of filtration better than none? I'm not sure; I've heard that the wearer will inhale harder and deeper with the mask, thus sucking in more of the small particulates into the deep recesses of the lungs. It's kind of like not 100% UV protecting sunglasses. Julien, am I right on that one or could you provide me with a valid link regarding said question? I'd appreciate it.
Julien wrote : re
I never heard that before. I looked on internet and in few scientific articles databases and I could not find anything, one way or the other...
wxc wrote :
Hi TK. What was your conclusion when it came to air purifiers? Did you opt for a HEPA one, or did you find a better solution? I'd be really interested to hear your ideas.
hawei wrote : PM 2.5 against life expectancy
See the "Fine-Particulate Air Pollution
and Life Expectancy in the United States" issued by the New England Journal of Medicine & the relevant report "Moins de particules fines, plus d'espérance de vie" issued by the French Newspaper LE MONDE of 03.02.09... it is really time for big cities in China to focuse on the pollution analysis in PM 2.5 & the ways to reduce its drastic effects.
TK wrote :

I did go for a HEPA, but not one of the local Yadus which are barely effective. After debating between an IQAir and Alen A375UV, I ended up with the Alen. Big difference between these and the cheaper versions is that they are properly sealed (will actually filter air), hit numbers in the high 99 percentile, and both include other filters which kill spores plus bacteria.
I have been running it for 2 months now and am really happy. My lungs are much clearer & I barely cough unless I am out all day long. I also added a vapor style humidifier and that helped soothe my chest. Really really reccomend these 2 machines if you are planning on staying in Beijing for anything longer than a year.

Julien, thanks for your input on the masks. Am going to look into it more. I'm picking up a sportbike in a couple of months and am weighing my options for under the helmet. I was pushing towards some industrial type filters but I don't think they would fit in my helmet. RESPRO may be my b...
SU wrote :
Regardless of what machine we buy, i am sure it will work. I ended up going with the Blueair because of the price and many reviews. Yes, all i hear is this IQAir, but i don't want spend my whole life savings keeping up with filter changes. Another thing, i need one of those mask :)
Louie wrote : Choosing an air filter
Great to come across this informational website! I run an indoor environmental quality services company and we spend a lot of time testing air (and water) for residents and companies in Shanghai.

One of the most frequent questions we get is around what type of air filter to buy. I eventually ended up writing an article on the subject: http://www.purelivingchina.com/2010/12/how-to-choose-an-air-filter-purifier-in-china/

As someone mentioned here, HEPA filters in theory all filter 99.97 of particulates up to 0.3 microns in diameter. The width of a human hair is about 150x in comparison. What separates the good filters from the 1000rmb Yadu specials is the ability to circulate the air to provide clean air for the entire rated space. Then there are other technologies such as UV to kill microbes and bacteria, PCO to oxidize gases, carbon to eliminate odors, etc.

We also get a lot of questions about what masks to use when you're outdoors, so we will be doing a comparison of the mo...
Write comment
Security Image
Please input the anti-spam code that you can read in the image.
< Prev   Next >