Respiratory Protection in Asia – The Truth About Masks Used
Do you want the truth? Think you can handle the truth?
Well, the truth is the following three methods used to protect yourself from breathing in contaminated air will not provide you any protection at all!
Sorry to be the bearer of bad news, however, this blog is not all about sunshine and rainbows
This blog is intended to shed some light on the “masks” commonly used to protect people from airborne hazards in Asia, and tell you why they don’t work.
NOTE: The information presented below is not based on rigorous filtration efficiency testing repeated in a laboratory. The information presented answers one simple question i.e. “will that mask protect me?” It’s pretty simple to answer, either it will or it won’t protect you.
In Part 3 of this Respiratory Protection in Asia Series, we explored the Principals of Protection. We now know that a mask will only protect you when all of the air that goes into your lungs passes through a filter that removes all of the bad stuff from the air. To achieve these two fundamental things need to occur:
1. the filter media has to be designed and tested to prove that the contaminants you are protecting yourself from will be removed from the air; and
2. all of the air has to pass through the filter before it reaches your lungs – that is, no bad air is can pass through the filter or travel through any gap.
So let’s apply these principles to the mask most commonly seen to be worn in Asia……the good old Medical Mask.
Firstly what is a medical mask?
In the 1890’s a German bacteriologist and hygienist, by the name of Carl Flügge discovered infectious diseases such as tuberculosis and cholera could be transmitted through droplets released from people’s mouths and noses (AKA Flügge droplets) . This discovery lead to the development of the first medical masks consisting of gauze strips placed over the wearer’s mouth. It is believed French surgeon Paul Berger was the first to wear a surgical mask while operating in 1897.
These days, despite the introduction of immunisation and antibiotic drugs, used to control communicable diseases and infection such masks continue to be used for purposes of:
– limiting the transmission of infective agents from staff to patients during surgical procedures;
– protecting the wearer against splashes of potentially contaminated liquids; and
– reducing the risk of spreading infections, particularly in epidemic or pandemic situations.
Okay, so let’s apply the respiratory protection principles to test the Medical Mask:
Will the mask filter remove the airborne contaminants?
No, the mask will not filter airborne contaminants. Why? because fundamentally the medical mask is designed to stop germs released by the wearer from reaching the outside world – – they are not designed to stop airborne contaminants from the outside world getting in!
Will the mask fit the wearer’s face so no gaps between the mask and the wearer’s face are possible?
What about the designer masks you ask? Surely they must protect you, they look so good.
I am told that the designer masks are preferred over the medical masks, however, they are more expensive and, therefore, are less common. I have also been told that an added benefit of these masks is you can wash them and they will last up to 3 or 4 months.
So what are the masks made up of?
So let’s apply the respiratory protection principles to test the Designer Mask:
Will the mask filter remove the airborne contaminants?
The simple answer is no
Why’s that you ask? Well, the material the masks are made of allows airborne contaminants to pass through and into your lungs. In Part 3 of this series, we demonstrated the size of airborne particles (PM10 and PM2.5) in comparison to a human hair. The photo on the left shows a human hair that has been pushed through the mask to demonstrate how big the holes are in the material are. The photo on the right shows how the large holes can be seen with the naked eye.
Will the mask fit the wearer’s face so no gaps between the mask and the wearer’s face are possible?
What about covering your and mouth and nose with your hand for protection?
It’s actually quite difficult to apply the respiratory protection principles to this method of protection. The human hand is not pervious, i.e. air cannot pass through your hand.
Now, hypothetically speaking just say you were able to seal off your mouth and nose with your hand, then how would you actually breathe? Let’s face it, to breathe in clean air we need to remove the bad contaminants, to do this we need a filter. The hand is not a filter. Once you remove your hand away from your face you will continue to breathe in the contamination.
Don’t miss the final blog in this 5 part series where we take a look at the real challenges for protecting persons lungs in Asia.
Respiratory Protection in Asia – Principles of Protection
Last year the World Health Organisation (WHO) reported that sufficient evidence now demonstrates air pollution to be the world’s single largest environmental health risk, contributing to 1 in every 8 deaths globally (approx 7 million people per year).
I have been working in Asia for some months now and have certainly noticed the significant environmental pollution. The other thing I have noticed is the “face masks” worn by the Asian population.
With all due respect, I do have some concern regarding the “masks” I have witnessed in use, particularly as the general perception is they will protect against dusts, chemicals and other biological hazards.
This blog is intended to simply explain how a “mask” works and how it actually protects you from all of the bad stuff in the air!
Let me provide you with a simple explanation of how clean air gets into your lungs and how bad air can be kept out.
Now, imagine billions of tiny little pollution particles that continue to float around in the air. Under a microscope, they usually look like this little creature
Now the aim of protection is to stop these little creatures from getting into your lungs
Sounds easy enough, right? Well, let me tell you it’s not!
You see when you wear a protective mask there will be a myriad of things that influence whether or not those little creatures will get into your lungs. Fundamentally to provide you with protection, the mask must:
— remove creatures of all sizes;
— remove creatures of all chemical states (gas, solid or liquid); and
— fit your face.
Let’s have a look at these more closely.
Whoever said size doesn’t matter was wrong! You see the tiny creatures that get into your lungs and hurt you are typically not visible to the naked eye, that is you won’t be able to see them!
Dust (or “particulate matter” as occupational hygiene nerds like to call it) comes in many sizes. The fact that it is floating in the air demonstrates how small it really is, you see the heavy particles will fall out of the air leaving us to deal with the small ones.
Now here’s two facts for you to consider:
1. the smaller the creature, the deeper it will go into your lungs
2. the deeper the creature goes into your lungs the less likely it will be for the creature to ever come out
Well, how small does it have to be you ask?
Let’s look at the pictures below. For us to even breathe in a creature it would have to be around about 10μm (AKA PM10), for a creature to get deep into our lungs it will need to be around 2.5μm (AKA PM2.5). Now let’s compare these sizes to the size of a human hair.
The microscopic image of the hair on the left below demonstrates the diameter of a human hair to be 60μm. Now looking at the diagram on the right we can compare the size of each creature to the cross section of human hair. Pretty small right?
So for a mask to even work it would need to include filter media that would capture even the smallest particle.
CHEMICAL STATE (GAS, SOLID OR LIQUID):
Creatures that “float around” in the air don’t just include particulates. Creatures come in many different forms and include liquids (think of vapours coming from a petrol tank) and gases. It is important to understand how the mask will actually adsorb the creatures made up of liquids or gases so that they don’t pass through and travel into your lungs. The discussion above regarding size continues to be relevant even when discussing the chemical state of each creature.
Think of the protection you need in the form of an umbrella that you were standing underneath. Your goal is not to get wet! If your umbrella was made of cotton (similar to the shirt on your back) and it started raining, would you get wet? Have a think about it.
It’s important to understand what you are protecting yourself from, whether it be a gas, solid (particulate) or vapour (liquid) so you know that the mask you are wearing is actually not going to let the little creatures travel across to the other side so they can get into your lungs. This is the very reason why different filters are used to capture different types of creatures. It is also important to note that sometimes no matter how good your mask is there are just some creatures that cannot be captured with a filter, for example, carbon monoxide (CO).
Sometimes people say to me that they don’t like wearing a mask because it makes their glasses fog up. Well, I can tell you there is only one reason for that – – – – the mask actually doesn’t fit!
So your still a little confused when I talk about a mask “fitting” you? Well it is simple, the mask you wear is designed to cover both your mouth and nose as these are the two locations air will go in and out of your body (other than farting of course!). We know that all of the air needs to pass through a filter to remove all of the bad creatures, therefore if there is a gap between your mask and your face, then bad air will enter your lungs, its that simple!
Mask seal against the wearer’s face
What’s not simple is actually getting a seal between the mask and your face, that is getting your mask to fit! Remember the picture showing the tiny size of the creatures in comparison to a human hair? Well, the picture below demonstrates how something as simple as facial hair will create a gap between a mask and a person’s face resulting in a broken seal. Once this seal is broken it is easy for the little particles to travel through the gap and into the lungs.
— the material the mask is made from;
— the shape of the persons face;
— features such as a persons nose;
— the size of the mask; and even
— chewing and talking!
So what do I need to remember?
The only thing I want you to remember from this blog is never assume a mask will protect you.
A mask will only protect you when all of the air that goes into your lungs passes through a filter that removes all of the bad creatures. To achieve this two fundamental things need to occur:
1. the filter media has to be designed and tested to prove that the creature you are protecting yourself from will be removed from the air; and
2. all of the air has to pass though the filter before it reaches your lungs – that is, no bad air is can pass though the filter or travel though any gap.
Don’t miss the next blog in this 5 part series where we take a look at and apply the above principles to the following three types of respiratory protection or “masks” commonly used in Asia to protect against all sorts of airborne health hazards.
Respiratory Protection in Asia – Do we actually need protecting?
Okay, so Part 1 of this series introduced you to “masks” I have observed to be used in Asia to protect against contaminated air. I must admit I have never seen so many people wearing respiratory protection in some form or another in my life. Which raises the questions “is there really that much contaminant (AKA “bad stuff”) in the air?” and “do we actually need protection?”
Since working in Laos, I have noticed significant changes in seasonal air quality. I arrived in October, the end of the rain season. It is now the dry season and rural populations are preparing land to plant rice by slashing and burning all vegetable matter (termed by scientists as “biomass burning”). It is obvious to anyone with eyes that the burning activities significantly burdens the air with contaminants. The pictures below, taken at the same location show the visible difference in the seasonal air quality (October 2014 and April 2015).
Smoke-filled air from biomass burning 05.04.2015
So what are the facts?
Well, the World Health Organisation (WHO) reports:
– in 2012, 1 in 8 of all global deaths (approx 7 million ppl) was resultant of air pollution exposure; and
– sufficient evidence now demonstrates that air pollution is the world’s single largest environmental health risk.
So what is “Air Pollution” then?
Indoor Air Pollution – The Facts:
Pollution and Exposure Source: Pollutants generated from open fires and simple stoves used to cook and heat the home using solid fuels such as wood, crop wastes, charcoal, coal and animal dung. Such fuels produce small soot particles that penetrate deep into the lungs. In poorly ventilated dwellings, indoor smoke can be 100 times higher than acceptable levels.
Population Affected: Approx. 3 billion globally. Exposure is high among women and young children in low and middle-income countries, who spend the most time near the domestic fire.
Health Outcomes: 4.3 million premature deaths annually.
Outdoor Air Pollution – The Facts:
Pollution and Exposure Source: Pollutants arise from household solid fuel fires, motor vehicles, agricultural waste incineration, forest fires, certain agroforestry activities (e.g. charcoal production) and power plants. Exposure concentrations differ by geographic areas and time spent in various settings.
Population Affected: Persons who live in the Western Pacific and South-East Asia regions disproportionately experience the burden of outdoor air pollution accounting for 88% of all premature deaths globally.
Health Outcomes: 3.7 million premature deaths annually.
NOTE: In 2013 an assessment by the International Agency for Research on Cancer (IARC) concluded that outdoor air pollution is carcinogenic to humans, with the particulate matter component of air pollution most closely associated with increased cancer incidence, especially cancer of the lung.
Okay, air pollution is a real issue for people who live in the Western Pacific and South-East Asia regions:
When combined, the population of the Western Pacific and South East Asian regions approximates to 3.2 billion people. Almost half of the world’s population!
Do we need protecting? Yes! or as the Laos would say “man lao”!
READ MORE FROM THE RESPIRATORY PROTECTION IN ASIA SERIES:
Respiratory Protection in Asia – What’s the Deal?
Okay, so I have been working in Asia long enough now to recognise that many people of the general public and workers get around wearing makeshift respiratory protection.
So I asked one of my Lao colleagues “what are those things people wear on their faces”? She simply replied “masks”.
So when you try to protect yourself from “bad air” in Asia what do you use? Well I have observed three typical methods that include:
1. Wearing a medical “mask”
2. Wearing a “designer mask” purchased at the local village
3. My personal favorite – Covering your mouth and nose with your hand
Apparently the last method is quite effective when riding a motorbike!
Firstly I have to acknowledge the willingness of the Asian population to wear some form of protection in an attempt to stop them from breathing in all the bad stuff that fills the air. A cultural characteristic I rarely witness in Australia!
However and with all due respect I do have some concern regarding the “masks” I have witnessed in use, particularly as the general perception is they will protect against dusts, chemicals and other biological hazards.
So what’s the big deal and why would I be blogging about this? Well, to reduce harm to persons requires controls to be implemented. Firstly, no control will be bullet proof unless the hazard is eliminated. Secondly, to actually know if a control will work (or not) requires an understanding of its limitations.
This 5 part blogging series aims to promote awareness of the limitations of controlling exposure to “dirty air” in Asia when using the three methods described above. Tune in tomorrow for Part 2 to learn if we actually do need protecting!
Welcome to my inaugural blog.
Some of you may have noticed that I was a participant in the initial round of monitoring for the Newcastle ColorRun. Why go back for more you may ask? Well I claim I am doing this in the name of science and for the greater good… believe that if you will 🙂
The Brisbane ColourRun took place on a sunny Sunday in May, and I was keen to see how the QLD run compared to the three NSW runs I had completed previously (some sort of state of origin maybe).
Generally, I saw less “Color” thrown at participant faces and above shoulder height. Most volunteers were well versed in aiming the Color at chest height and the amount of Color being thrown at us appeared to be less than that experienced in Newcastle (and Sydney). I didn’t get as many direct hits with the Color on the sampler as I had in Newcastle either (those Novocastrians do know how to throw a Color party!).
I saw a number of volunteers wearing respiratory protection in the form of a P2 disposable respirator which was a pleasant change from previous runs, where volunteers were observed to be covered in Color and stayed within the “Color Zones” for up to 4 hours without any form of respiratory protection.
The sampling methodology was the same as that implemented for the Newcastle ColorRun, with all samples pre and post calibrated in accordance with AS3640 (2009). Four willing participants wore sampling pumps throughout the run and whilst they were in the Color throw area at the end of the run. All samples ran for approximately 2.5 hours with exposure for the remainder of the day estimated to be zero as per the methodology used previously.
The table below lists the results in relation to the Workplace Exposure Standard.
|Participant||Result (calculated over 8-hours, assumed no exposure for remaining time after the ColorRun)||Exposure Standard|
|Renee||1.5 mg/m3||4 mg/m3|
|Dani||0.8 mg/m3||4 mg/m3|
|Evan||14.2 mg/m3||4 mg/m3|
|Kristy||14.7 mg/m3||4 mg/m3|
Half of the samples exceeded the exposure standard. This correlated well with the samples collected in Newcastle where 3 out of 5 samples exceeded the exposure standard.
In order to answer the initial question “Is the ColorRun hazardous to your health?”, I first combined the Brisbane results with the Newcastle results and performed statistical analysis of the data. As was the case with the Newcastle dataset, the 95th percentile was calculated to be well over the Exposure Standard. This again was due to the high sample results and the large degree of variability in the data set.
So what does this all mean? These results confirm that overall, although it is fun, participating in the ColorRun is hazardous to your health. However…the results demonstrated that some participants fared better than others. It was interesting to note each participants strategy during the run influenced the amount of Color inhaled.
For example, Dani ran the whole race and did not pause in the Color Zones, which resulted in an exposure well below the Exposure Standard. The same can be said for Renee who jogged the course and partook in the Color throw but was not overly covered in Color. On the other hand, both Evan and I jogged the course and willingly were covered in Color dust on all occasions, finishing the course covered in Color Dust.
Further to the recommendations made previously, it could be suggested that the way in which you approach the ColorRun course will influence the amount of Color you may potentially inhale. If you make a diligent effort to not linger in the Color Zones and progress directly through these with volunteers throwing Color at only chest height, you may well be able to complete the ColorRun with your exposure falling below the Exposure Standard.
Speaking from personal experience, the Color Dust is an irritant and it does clog your nose, mouth and eyes if inhaled or ingested and symptoms last up to three days. So consideration should be taken prior to participating in the ColorRun, in particular for those with young children or asthmatics.
If you do choose to participate in this event in the future, then take caution when going through the Color throws at each kilometre, which would include skipping them entirely, or wear respiratory protection in the form of a P1 or P2 disposable dust mask. I also recommend skipping the final colour throw entirely as this is where the majority of Color Dust is inhaled when Color is thrown into the air on 20 minute intervals.
The implementation of respiratory protection for volunteers at the Brisbane event was a welcome sight, but it appeared that this was worn on an individual basis (not everyone had them on) and volunteers may not have been educated in the health effects of breathing in all that Color Dust throughout the day (based on the fact some had respirators and some didn’t). Further education and information is recommended for both volunteers and participants alike to ensure people are aware of the potential risks to health prior to partaking in these runs in the future. As a side note, there are a number of items that need to be implemented when you provide respiratory protection to workers including fit testing, maintenance, and training in their use and limitations. Australian Standard 1715 is a good place to start if you’re unfamiliar with all of this.
The biggest risk to health appears to be for the volunteers based on the time they spend in a visually dusty environment. While we do not have personal exposure data to demonstrate their exposure above the Workplace Exposure Standard, they appear to be group at highest risk, and it is reasonably anticipated that exposure would exceed the Exposure Standard (and possibly above the protection factor afforded by the disposable respirators in use…they will only protect the volunteers up to a concentration up 40 mg/m3 if fitted and worn correctly). In accordance with the Work Health and Safety Regulations (which apply in both NSW and QLD), workers must not be exposed above the Exposure Standard, and if it is not certain on reasonable grounds whether the Exposure Standard will be exceeded, then air monitoring (personal exposure monitoring) must be performed. Out of the four ColorRuns I have participated in, I have not seen any volunteers set up with personal pumps to measure their exposure. This would be a key recommendation for event organisers to consider to both protect the health of volunteers and to ensure compliance with the Work Health and Safety Regulations. (Side note: it is entirely possible that this assessment and monitoring has occurred on other ColorRuns that I have not participated in!)
If any other occupational hygienists plan on attending a ColorRun in the future, I encourage you to perform additional exposure monitoring as additional data will provide more certainty and confidence in the results obtained to date.
Following on from the exposure assessment we performed on runners in the Newcastle ColorRun, we are lucky enough to have some more volunteers who ran the #happiest 5k in Brisbane recently and took some more samples.
So will the results be the same? Will they continue to show that participating in the ColorRun is hazardous to your health? The samples are in with the lab at the moment so we will just have to wait and see…our newest guest blogger, Kristy will bring us the news as we get it!
Is the ColorRun hazardous to your health? That is the question I set out to answer, yet unfortunately, like most things in occupational hygiene, getting the answer wasn’t that simple!
I’ve provided details on the methodology I used to collect the samples previously (and what it looked like during the run), but I need to explain the limitations in the data I collected. It’s important to know the limitations of any study before you accept the conclusion…so going against the way that popular media typically reports scientific studies and I’m going to give you some of those limitations first:
- Firstly, only five valid samples made it out of the run. This isn’t too bad, but I had hoped for at least 6 samples so I had greater confidence in the data. As it stands now, I have highly variable results and a relatively small data set…not what I really want. But like my 7-year old says, “you get what you get and you don’t get upset!”.
- Then there was the case where some of us suffered a direct hit from a colour throw (when the Color Run volunteers threw the dust right in our face for example…which happened twice). This resulted in small chunks of dust being left on top of the sample filter. They would not be representative of what you would breathe in (you might swallow them perhaps…but not inhale). However those “chunks” of dust dried up and actually rolled off the filter, so they weren’t analysed. The NATA-accredited lab even reported that the samples, “contained large amounts of loose particulate matter that was not all able to be weighed with the filter. Results may be biased low”. So if anything, these results are lower than they probably are…not the other way around.
- We only sampled for 2.5 hours on average, and the exposure standard is based on an average over an 8-hour workday. For direct comparison purposes, I have assumed that the remaining 5.5-hours or so were spent in a dust-free environment, but I didn’t measure it. So again, these results are biased low (so they are conservative).
- We are not workers and so the “exposure standard” legally doesn’t apply to us as such. But it does apply to the volunteer workers throwing the colour around and standing in a haze of dust for 2.5-hours. If our results appear shocking to you, just imagine the dose that they are getting and the impact to their health.
So let’s get down to the good stuff…the sample results. I’ve listed them in the table below in relation to the exposure standard. Remember that exposure standards represent airborne concentrations, which according to current knowledge should not cause adverse health effects nor cause undue discomfort to nearly all people. They do not represent “no-effect” levels that guarantee protection for everyone because of the variability in susceptibility between individuals. Therefore there may be a small proportion of people who may suffer mild or transitory discomfort at concentrations around, or below, the exposure standard. An even smaller number may exhibit symptoms of illness. Exposure standards determine whether a potential exists for over exposure, and associated ill health effects.
Three out of five samples exceeded the exposure standard, so I wasn’t off to a good start.…but to answer my question, “is it hazardous to your health”? I wanted to use statistics. There is uncertainty in all data, yet I wanted to see 95% of the data be below the exposure standard. I won’t bore you with the statistics, but the 95th percentile was well over the exposure standard. This was due to both the high sample results and also the high degree of variability in the data set.
|Runner||Result (calculated over 8-hours, assumed no exposure for remaining time after the ColorRun)||Exposure Standard|
|Kel (ran with 2 x four year old boys)||29.0 mg/m3||4 mg/m3|
|Kym (ran with 1 x three year old son)||1.1 mg/m3||4 mg/m3|
|Mel (ran solo)||22.5 mg/m3||4 mg/m3|
|Kristy (ran solo)||84.2 mg/m3||4 mg/m3|
|Me (ran with a 7 year old daughter)||0.8 mg/m3||4 mg/m3|
So what does it all mean? These results demonstrated that participating in the Newcastle ColorRun was hazardous to our health.
Some of us as you can see fared better than others. We all ran the same course in roughly the same amount of time. The amount of flour dust we inhaled though was more due to luck (or lack of) more than anything else. It’s almost impossible to not get covered in dust if you run through a colour station or go to the colour throw at the end.
Like any good occupational hygienist I need to provide you with a list of recommendations based on the data collected. So here are some of my recommendations for future participants of the Color Run:
Seriously consider your need to participate in this event. If you suffer from allergies, or allergy-type symptoms such as coughing, wheezing, shortness of breath, or if you suffer from asthma, or if you are considering taking babies or small children, then this is especially important.
If you do participate, then take caution when going through the colour throws at each kilometer, which includes skipping them entirely (run around them up wind), or wear respiratory protection. I also recommend skipping the final colour throw at the end and the optional trip to the “Cleaning Zone”.
It’s a pity that this event is targeted at families and for kids to #runwithmum and yet the health risks associated with participating in this event are understated. I have no problem with risky activities…I just think that people should be provided with all the information so they can weigh up the risks and make an informed decision for themselves. I would recommend that the organisers of the ColorRun provide the Safety Data Sheet for the “color” on their website and to engage a competent person to provide an updated commentary for the public on its meaning. It is not fair for parents to have to individually contact the organisers, only to be told that “breathing small amount of this material is not likely to be harmful“. You should be told the health effects of the colour, the concentrations at which you may experience those health effects, and things you can do to reduce your exposure. Most importantly you should be made aware that some people are more susceptible to developing illness related to exposure. That would be more useful than telling me it’s “gluten free“.
Spare a thought also for the volunteers who were not provided with respiratory protection and stayed within those colour stations (dust clouds) for over 2-hours. If you think our results were high, then their exposures would be far greater. Of course this is only a guess as I didn’t measure them (but it’s based on an educated observation!). I’d suggest there is a significant risk of exposure to flour dust in excess of the Workplace Exposure Standard and controls are needed to reduce that exposure. I recommend that one of those controls should be to perform a personal exposure assessment for volunteer workers.
There were a lot of people running with tiny babies and small children (including us). It’s not worth it, seriously. It’s hard for me to say this as my daughter LOVES it, but sometimes it’s just not worth the risk. We’ll just find another mum-daughter bonding activity…one that isn’t hazardous to our health.
Still not convinced? Well it’s a big call to say all of this on just 5 samples, so I’m lucky that I’m not the only Occupational Hygienist out there with a bunch of sampling pumps. The more samples we can collect to add to the data set will provide more certainty and confidence in these results. I will update these results and recommendations with additional validated data as it comes in…so stay tuned!