“太热了，只想靠空调续命。”
可是PM2.5超标了，空调会不会把外面的雾霾带进来？
虽然很热，但是雾霾可没放暑假
这段时间北京很热，都有人可以在车上烤鱼了！
可是，雾霾没放暑假，而且今天PM2.5又超标。
虽然这不是“空气末日”的水平，但是附近的大楼已经开始模糊、看不清楚了。
不知道大家有没有和我同样的担心：
天气这么热，雾霾又严重，如果开空调，它通向外面的管子，会不会把雾霾带进家里？
是不是少开点空调会好一些呢？
这也是我曾经非常担心、好奇的问题：
壁挂式空调会不会把外面的PM2.5吸进来？ 如果是这样，雾霾天就不能开空调了吗？
我的回答是：不是的。
我用下面三点来解释：
1、测试空调吹出来的空气
首先，我做了这个测试：
在室外雾霾特别严重的时候，我打开空调，然后把测试仪放在空调的出风口。
结果室内的颗粒污染跟整个房间的平均空气都差不多。（查看测试视频）
这说明空调没有把室外的空气吸进来。
2、测试开空调前、后的空气
接着，我又做了一个小测试：我先打开测试仪30分钟，记录基础数据。然后，再打开空调30分钟。继续记录。
结果呢？我发现开不开空调基本上没什么区别。
下图是开空调一次测试的结果：
下面是我在我房间做了七次测试的平均效果：
可以看到，颗粒污染基本没什么变化。
事实上，2.5微米颗粒还下降了一些。
这可能是因为空调内有滤网，或是随机变异的结果。
3、空调的工作原理
普通的壁挂式空调的确有个管子，连接了室内、室外，但是这个管子是用来循环冷却，而不是将室外的空气带进来的。
那空调吹出来的冷气到底是从哪来的呢？
如果你仔细的看看你的空调，你会发现：空气从顶部进入，然后经过冷凝管，最后从正面吹出冷气。
它循环了室内的空气，并没有把室外的空气带进来。
所以， 结论是什么呢？开空调就没有吸霾危险了？
等一下，我家有中央空调！
如果你的家里有中央空调，情况就复杂一点。
以上的测试都是针对壁挂式的空调，那中央空调呢？
有的中央空调并不会把外面空气带进来，只是循环室内的空气。
而且，有的中央空调里有滤网，可以进行过滤；有的则没有滤网，就会把外面的空气带进家里。
那我们怎么才能知道自己家里的中央空调属于哪种呢？
了解你家的中央空调
1、如果可以，看一下中央空调系统。里面有滤网吗？有通外面的管子吗？
2、问一下物业（如果他们知道…）。
3、测一下出来的空气。
我现在住的地方有中央空调，我问了物业，物业工作人员说它只是循环空气。
但是，我觉得做测试才是最靠谱的方式，所以我做了测试。
结果发现，没开空调的时候，0.5微米颗粒大概是400。开了中央空调以后，就升到了1千三百多。
所以我猜这个系统把室外的雾霾带进来了。
划重点：空调会把外面的雾霾吸进来吗?
空调不会把外面的雾霾吸进来。但中央空调不一定，需要确认一下。
如果你家里有中央空调，也值得测一下。
Smart Air 提供专业科学的测试给大家
公开数据
空调测试原始数据是公开的：
Hello I’d like to make a few comments and a question. I have a split air condition system similar to the one on this pictures and I find that it does not bring in air from the outside. However you may notice they are coming in certain places for example I have a sliding balcony door that seems to have a little bit of air seepage. I noticed this because I have a neighbor across the street who regularly is burning stuff in their furnace. I guess it’s like a wood stove. Sometimes I can catch a whiff of what they’re burning and it’s not a good smell. I attribute this to some of the seepage in and around the windows and doors of my old house. So what I’ve done is bought some free-standing air filter machines with HEPA filters. It seems to help. Recently I bought a what’s can be described as a dust filter to cover the HEPA filter of the air machine. In one of the photos they showed this I guess it’s a p.m. 2.5 mesh being used to cover the air intake of the split AC. I haven’t found any 3M filter for the split AC in this country that I’m in. So I just put it on today it seems to be working okay what I’ve noticed is though there’s a little bit of a reduced output from the machine as far as air flow. I’m pretty bad about cleaning the screen though it’s supposed to be cleaned every 2 weeks and I typically clean it maybe every 2 months or 3 months. It’s kind of difficult for me to get up on the ladder. So I’m trying to 2.5 pm mesh as an extra buffer to keep the dust from accumulating in the screen. They called the screen a filter but I hesitate to call it a filter because it doesn’t really filter much except large dust particles. Do you think there could be any potential harm to the machine from the reduced airflow through the mesh? I think if there’s any mechanical problem I can just remove the mesh before the service people come. Anyway I’m going to keep it like this because I think it’ll also make cleaning the screen easier. Cheers!
Is there any product that prevents air pollution for office/residence use?
Definitely, MD. Abaduzzaman! Air purifiers are simple, effective ways to filter air pollution in the office and at home. Best of all, there’s nothing fancy about them and they’re not expensive!
For office environments, a large-size air purifiers that have low noise levels would work best, for example the Blast air purifier Smart Air offers. Smaller, more compact air purifiers are ideal for home living rooms and bedrooms.
I have found that of course you can buy filters you easily install in your split room air con units. 3M makes them. You just buy the filter and cut to size.
Hello Thomas, my english is not so good 🙂 I m Marc from Germany, living from august 2018 in Malaysia Johor Bahru now and for one, two more years.. Our son is in grade 8 in international canadian school. The government makes measurements by API. …i use own in germany bought professional device for AQI, 2,5 etc. When for ex. the App “Air Visual” shows Singapur(Johor is directly at Singapur!) with 150, Malaysia is only 60..70…so i think Malaysia goverment is giving fake measurement. School is closing from 200API of Malaysia goverment!!! My Device was on 220 in classroom of school and outside! Principal said: Can only close when goverment said. And goverment said: We have 110 today :-)))))
Air Visual also was 200. But school area is no meassurement point. Next is 30 kilometres away!
I m in parents council and i m fighting for air cleaners in classroom…or new Aircon with 2,5 mirometer filters. I ask many experts, all said, if i would put 2,5 m filter in normal Aircon, the aircon will go damage.
And i think school should have own device for air measurement! But school said: Why? only goverment decide…
Any good ideas? Thank you very much!
Marc
Marc-Ingo Nölting
43, Jalan Ambang 1, Horizon Hill, Iskandar, 79100 Johor Bahru
I’ve found that the AC wall unit itself doesn’t bring in pollution but the hole in the wall where the electrical wiring and drainage tube are located can allow outside air in. If you are detecting air pollution from the AC unit then it might be the hole used for the wiring and tubes from the unit.