WHO air quality guidelines and how it affects your Indoor air quality

Created Tuesday, 19 April 2022

<p class="MsoNormal"><span lang="EN-IE">The World Health Organisation has revised
their Air Quality Guidelines. <o:p></o:p></span></p>

<p class="MsoNormal"><span lang="EN-IE">This is a very significant update,
particularly with the pandemic, so we take you to the source to discover more
about the guidelines, the new thresholds for the air that we breathe, and how
the new standards affect indoor air quality standards in your building.<o:p></o:p></span></p>

<p class="MsoNormal"><span lang="EN-IE">Our guest Tobias Zimmer was involved in
setting the guidelines which are taking effect globally. In our conversation,
topics we discussed included:<o:p></o:p></span></p>

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Symbol">·<span style="font-variant-numeric: normal; font-variant-east-asian: normal; font-weight: normal; font-stretch: normal; font-size: 7pt; line-height: normal; font-family: "Times New Roman";">        
</span></span><!--[endif]--><span lang="EN-IE">Tobias’ role in helping set the
WHO guidelines<o:p></o:p></span></p>

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auto;text-indent:-18.0pt;mso-list:l0 level1 lfo1"><!--[if !supportLists]--><span lang="EN-IE" style="font-family:Symbol;mso-fareast-font-family:Symbol;mso-bidi-font-family:
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</span></span><!--[endif]--><span lang="EN-IE">How these guidelines are agreed<o:p></o:p></span></p>

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</span></span><!--[endif]--><span lang="EN-IE">Why this update is so
significant<o:p></o:p></span></p>

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auto;text-indent:-18.0pt;mso-list:l0 level1 lfo1"><!--[if !supportLists]--><span lang="EN-IE" style="font-family:Symbol;mso-fareast-font-family:Symbol;mso-bidi-font-family:
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</span></span><!--[endif]--><span lang="EN-IE">Adoption and enforcement
worldwide<o:p></o:p></span></p>

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</span></span><!--[endif]--><span lang="EN-IE">The biggest changes you need to
know<o:p></o:p></span></p>

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text-indent:-18.0pt;mso-list:l0 level1 lfo1"><!--[if !supportLists]--><span lang="EN-IE" style="font-family:Symbol;mso-fareast-font-family:Symbol;mso-bidi-font-family:
Symbol">·<span style="font-variant-numeric: normal; font-variant-east-asian: normal; font-weight: normal; font-stretch: normal; font-size: 7pt; line-height: normal; font-family: "Times New Roman";">        
</span></span><!--[endif]--><span lang="EN-IE">Can your existing system handle
the change<o:p></o:p></span></p>

The Transcript

For your convenience, here is a 90% accurate automated transcript of the podcast.

Tobias Zimmer  0:01  
And that ended up with significant changes of several of the safe limits in both directions. On the one side, you have, for instance, sulfur dioxide, so to which they concluded that it's actually less critical than assumed before. But on the other side for several other pollutants, the changes have been in quite the opposite direction.

Dusty Rhodes  0:27  
Hello, and welcome to Let's Talk clean air our regular look at how clean air can affect the quality process for you and the workplace. On this episode, we're finding out about the New World Health Organization revised air quality guidelines and how they could impact your building or facility. My name is Dusty Rhodes and joining me to explain this is Tobias Zimmer who is deeply involved in the development of international standards, and acts as Vice President of Global Product Management and international standards at Camfil. Tobias Can you tell me firstly about the role that you play in setting the international guidelines?

Tobias Zimmer  1:04  
Yeah, for sure. I'm deeply involved in various standard committees that tackle air filtration, but also applications where air filtration is used. So I'm a member of the ISO TC 142, which is covering the ISO standards for all filtration applications. And I'm also involved in European standards for general ventilation. So the SAM TC 156. And in addition to that, I'm active in several, mainly European associations, but to take care about additional guidelines. For instance, we have the Euro event. So the biggest association of event at the ventilation industry as well as the AVR, European ventilation Industry Association. And last but not least, the Riva, which is the Association of engineers in Europe.

Dusty Rhodes  1:55  
Can I ask how these standards are formulated? What do you take into consideration when you're when you're setting the standards and the levels?

Tobias Zimmer  2:04  
Oh, that's really depends on the different standard and the application? If we're really talking about the application standards, for instance, in terms of ventilation, then of course, what are the protective goals? What do we want to protect by that standard by filtration? What is the outdoor air quality? Yeah, but also, what are the requirements of these different places? So for instance, obviously, the requirements of the hospital are quite different than in an underground carpark.

Dusty Rhodes  2:32  
Is there a lot of tooing and froing? And you know, anything when you when you're doing anything by committee? There's there's a lot of discussion, would it be the same when you when you're discussing these international standards and, and what levels to arrive at?

Tobias Zimmer  2:47  
Not that much, because there is a there's a broad public involved, there's the model, only the industry, then you will end up in this discussion. We also have a lot of universities and researchers involved in that. So it's very much fact based. And it's very technical comp, people in that committees. So it's really talking about facts about scientific base, and bring them back to a technical, logical and right dimension solution.

Dusty Rhodes  5:05  
Why are they rolling in particular, with guidelines for air quality?

Tobias Zimmer  5:19  
Because air quality as a concern, and there's more and more evidence, but the risk that we are exposed to by air pollution is much bigger than we assumed for the last decades. On the one side, the pollution levels in big parts of the world are actually going down, which is fantastic. But at the same time, we see that even those levels are serious hazard to health. And who just concluded when they published their new guidelines, that air pollution is the single most critical hazard to health. So it is more critical than unhealthy diet and smoking. If you look at the total effect on the world population,

Dusty Rhodes  6:14  
do you know why they have come to that opinion?

Tobias Zimmer  6:18  
Yeah, it's very scientific base. And that case, even  more than understand that committee, because it's really they just listen to scientists. So it's the groups of scientists sitting together, and reviewing the research results of the last years. And there is more and more evidence that at least for some of the pollutants, the hazard to health, even at much lower levels is still very high, much higher than assumed in the past.

Dusty Rhodes  6:46  
Now, when the WHO says these things, does everybody sit up and listen?

Tobias Zimmer  6:53  
Yeah, basically, a lot of people listen to who because they really they strictly stick to it. It is fact based at a science based, it's not politics.

Dusty Rhodes  7:02  
So listen, let's talk about the World Health Organization. They did have guidelines in place, and they've had guidelines in place. I think, since this is the 80s. There was guidelines before COVID. They've changed now, what is the difference?

Tobias Zimmer  7:16  
Yeah, let's talk about these air quality guidelines as your eye lift sets. The first edition was in 1987. So they regularly periodically to be more correct. update their guidelines to really the objective is to assist governments and the civil society to reduce the human exposure to air pollution and adverse effects. So these guidelines are really science based. I said before, it's really no politics in that it's scientists sitting together discussing reviewing the latest results. And that has given us a guideline to the society, they are not in themselves a mandatory standard. They are a pure guidance box sets, as they are fact based, science based and not in any way political documents. They have a very good reputation, and they are highly respected by standard committees, by many governments. So that's why these who are quality guidelines are quoted in several international standards. So that's in Delta the place to go. If there is any reference, what is the right level? WHO guidelines that that's the same to many national legislations? They refer to the W H O guidelines, because that's both all the hard facts.

Dusty Rhodes  8:43  
So even though that that guidelines, they kind of become the de facto standard, really?

Tobias Zimmer  8:50  
Yeah, the most reliable source for if you look for any limits, what is the safe limit for a specific pollutant, then this is the most reliable source you will find.

Dusty Rhodes  8:59  
Okay. Now there has been changes to those guidelines from the who, what do you think is the headline change? What's the biggest thing we should know about?

Tobias Zimmer  9:06  
Yeah, the biggest thing is, but there is a lot of changes to several of the safe limits. Why is that the case? It's quite simple. The last who air quality guideline is dated from 2005. So the new revision in September 2021, so just a few months ago, is 16 years later, and obviously was in 16 years. Science has a lot of new findings. And all that is now has been debated and it's all reported in that guidelines. So which is quite comprehensive documents. So you can clearly see based on what facts are this decision taken, but ended up with significant changes of several of the safe limits in both directions. On the one side, you have for instance sulfur dioxide sites so to, which like concluded that it's actually less critical than assumed before. So in that case, the safe limits went up quite significantly. So four times higher limit is acceptable. But on the other site for several other pollutants, the changes have been in quite the opposite direction. So if we see nitrogen dioxide, so no to very extreme example, the safe limits have actually been cut to a quarter. So coming from 40 micrograms down to 10 micrograms per cubic meter as a safe limit. Huge change. And even more important because it's very present everywhere on the globe, the safe limits for particulate matter have changed. So, particulate matter, there's two values they look at. So that's one of the PM 2.5, meaning particulate matter was the dial meter below 2.5 micro meters. Now, the second one is a more traditional older value of a PM 10. So particulate matter of below 10 micrometres. Both of these limits have been significantly reduced. And then the case of PM 2.5, has actually been cut by half. So instead of assuming 10 micrometres in a cubic meter of air is still okay. They cut it down to five micro meters per cubic meter. Because there is evidence, but even smaller concentrations are a serious hazard to health. And it would be a risk in permanent exposure. And as we are permanently exposed to the air, this is obviously a real threat. And it clearly shows that the smaller particles are, the bigger the risks of healthiness. But it was very clear on those guidelines. So that's why the PM 2.5 failures have been significantly more reduced than the PM 10 limits.

Dusty Rhodes  12:00  
So does this standard cover the indoor environment?

Tobias Zimmer  12:06  
That's not that easy to answer. The answer could be yes or no Yes or No both. Because if you really look at what's stated in the WHO air quality guidelines, they state, the guidelines are applicable to both outdoor and indoor environments globally. Sounds like cover all settings where people spend time reading that we would say definitely covers the indoor air as well. However, there it's not that easy, because indoor air and outdoor air a difference. Because the guidelines do not cover occupational settings. Unlike in the outdoor air where the there's a few free exchange was the environment whatever you create in particles, there's a lot of room around you. In an indoor space, the indoor air quality is affected by several other factors and parameters that need to be taken into consideration. So different to the outdoor air. You have, for instance, how much air do you bring in was the ventilation system, how many people are in the room. And what exactly the activity level of these people. So 20 people sitting in an office create a different level of air pollution than 20 people being active in a gym, or 20 people that really working in a workshop, it's a totally different scenario. And also machinery that's in the room, a printer or any other machine would have a significant impact on the indoor air quality. But means in a nutshell, that indoor space in indoor spaces, you need additional guidelines to ensure that you have a sufficient supply air, which technically would mean air you bring out from the outside into the room, too, to really ensure that your indoor air in the end is in line with the WHO air quality guidelines. And that's where other regulations like for instance, the eurovent 4/ 23 come into the picture.

Dusty Rhodes  14:09  
Well tell me about Eurovent 4/23. Is that a focus standard for indoor specifically?

Tobias Zimmer  14:16  
Yes, absolutely it is. And that's also not a new standard. Now the first edition of Eurovent 4/23 was published in 2018 was made by the product group air filters in the European Association. And this guideline very specifically deals with the selection of air filters according ISO 694 general ventilation applications. And the core concept of that guideline is that there is no such thing as a one fits all approach for all places in all areas of Europe. Because obviously the requirements are different depending on your place depending on the building type. Therefore, this year event 423 basically provides a simple dimensioning tool, taking into account just two key parameters. The first parameter is the local outdoor air. Because it's obviously it makes a difference if the air that you intend to bring into your building is highly polluted, or relatively clean. So in other words, if my building is located in the city of London, or in central Paris, I obviously need to filter the outdoor air at a totally different wave, as if my building will be somewhere out in the countryside. That's the first parameter. And the second one is what air quality do actually need. So what's the output parameter and the outdoor air? And what's the actual requirement inside? Obviously, in hospital, the air needs to be cleaner than in an underground car park or in the garbage rooms? Think that's quite logical, that can't be the same answer.

Dusty Rhodes  16:03  
So then when looking at the Eurovent 4/23 standards, have they changed then in line with the World Health Organization guidelines?

Tobias Zimmer  16:14  
Absolutely. Because the outdoor air in the 4/23 directly refers to the WHO guidelines. And if now the WHO guideline and the safe limits change. Obviously, that affects directly this guideline, Eurovent 4/23. And for that reason, there has been a very recent update of the guidelines that have been published in January 2022. And the main change is adoption to the new who air quality guidelines.

Dusty Rhodes  16:47  
And what is the main change in there from your point of view?

Tobias Zimmer  16:51  
Yeah, technically speaking, it's this changes made are quite simple and straightforward. But the impact of these changes is actually quite large. So let me explain like this. The guideline defines three levels of outdoor air quality, the so called Oda classes, outdoor air. So class one means the local levels of outdoor pollution, let's say pm 2.5. Pollution are below the WH o limits. So your outdoor air is relatively clean. Oh, Oda two means the outdoor air in your place, the PM 2.5 levels are up to 50% above guideline limits. So it's how to phrase it moderately polluted, if you like. Audio three, on the opposite says your outdoor air pollution is more than 50% above the WH o limits. So the outdoor air is heavily polluted. And of course, that would require much better filtration. That's basically what it says. So that's one side you have the ODA. And then on the other side, your side, okay, what supplier quality do I need. And the range isn't the same logic from supplier called sup 1251. For instance, being a hospital, very clean air. Two would be for instance, a normal office. And the worst things sub five would be the garbage room or the underground carpark which anyway, where you have a lot of exhausts, it will not be clean anyway on there. And that's the logic behind it. So as soon as the who changes the limits, of course, the limits for the ODA classes drop in the same way below who limits suddenly means for a PM 2.5, only 50% of the concentration.

Dusty Rhodes  18:55  
So when we're talking about the changes in limits, does what does this mean for somebody who's responsible for a facility or a building or an office block? Do they need to change their entire system? Or are air filters able to handle the change in levels? 

Tobias Zimmer  19:12  
Air Filters are absolutely able to handle that. But the overall effect is, as they would say, it's something quite positive. Because following these new European guidelines was a new who limits what actually leads to a better air quality in a majority of offices in all over Europe. Because if you look at it very, very in a very simple way, a normal urban area in Europe, Western Europe, Eastern Europe is even a bit more polluted. But in Western Europe, a normal urban area will be according the old standard would have been Oda to moderately polluted. Now applying the new who guideline limits. The waste majority of all cities in Western Europe turn into ODA 3 being heavily polluted because we are far above the safe limits, according WHO guidelines and that what directly result in a higher requirements for filtration. So we take an office as an example an office in an Oda to environment, the recommendation from the standard was before taken system efficiency for filters of ePM1 70%, but means the system so all filter filters you have, if you have two in a row, the accumulated efficiency of these two filters should be EPM 1 70, at least. So taken out 70% of particulate matter smaller one micrometres, which will be roughly equivalent to 80% of PM 2.5. Now, as the same building was the new classification is actually in audio three, the same requirement will be your system needs to be at EPM, one 80%. So, taking out 80% P one or roughly 90% of the PM 2.5. But still this is absolutely doable was a filter. It just increases the filter efficiency. You can basically install that in every existing ventilation system.

Dusty Rhodes  21:25  
There's an awful lot of detail in this subject, and you've explained it extremely well. But if people really kind of want to get into the details, where can listeners find out more about this online?

Tobias Zimmer  21:36  
The whole who quality guidelines can be downloaded, free of charge from the WHO website. Okay, it's available actually in two editions, the full edition, which is a few 100 pages, documents, or even an executive summary, which is just a few pages. For the technical details and for how to select the right filter classes based on these limits. The document the 423 from your event can be downloaded to loaded also free of charge from the euro band Association website.

Dusty Rhodes  22:09  
Excellent. And what we'll do is we'll include the exact links to the directly to the documents in the show notes. So if you're listening on your smartphone right now, just look in the show description. And the links are there ready and waiting for you? And you can check them out. Tobias, just before we head off for today, can I ask you kind of over the last two years? What's the biggest challenge that you have faced with COVID?

Tobias Zimmer  22:32  
The biggest challenge was actually educating the public but also many of the governments and institutions. Because it took awfully long to be honest, until people understood that COVID is an airborne problem to a big degree. Many of these things we could have tackled better if we had listened to earlier to what science told us even before you

Dusty Rhodes  23:01  
so listen to scientists more is the lesson of the day. Yes,

Tobias Zimmer  23:05  
in many cases it helps.

Dusty Rhodes  23:11  
Listen to bias. As always, thank you very, very much for such insightful and detailed information. If you'd like to find out more about this do follow the links. As I said in the show notes. You find them in the description of this podcast on your phone, or whatever device you're listening to us on. Our podcast today was produced by camfil a world leader in the development and production of air filters and clean air solutions. To stay up to date on how clean air can affect the quality process for you and the workplace. Do click follow or subscribe in your podcast player so that you can get the next episode automatically. Until then for myself to students. Thanks very much for listening and take care