10 Jan How healthy is the air you are breathing?
At Airconstruct we believe there is more to delivering effective maintenance strategies and project deliverables than reliable crisp cool air. The air we breathe in buildings is often compromised by either a lack of good filtration, inadequate fresh air being introduced into the building, and occasionally poor servicing practices and in some circumstances a combination of all three.
While there has been a major focus on Indoor Air Quality (I.A.Q.) in overseas markets for many years we don’t see much momentum in Australia. There are various publications, acts and regulations by different government bodies and they are often vague at best, they will say that the air must be clean, the airconditioning maintained and fit for human occupancy etc. but how do you know that it actually is? You would most likely have an air conditioning controller in your building that displays the current or desired temperature, but where is the cleanairometer? That’s right, there isn’t one.
Generally, the responsibility of an acceptable indoor environment will fall upon the Health and Safety Department or the safety professional. There was a booklet developed for government employees based on the decision of an Australian Industrial Relations Commission hearing in 1993 where Commissioner Smith stated in his decision:
‘I am satisfied that considerable impetus can be given to the monitoring of, and/or improving on, issues going to thermal comfort and air quality if designated health and safety representatives are firstly provided with an initial briefing on these issues; secondly, have a right to be advised of the maintenance routine and any problems associated with air-conditioning systems; and thirdly, can, within a reasonable time, have indoor temperatures checked…..In deciding in this way I am not suggesting that health and safety representatives should be trained to be experts in the field but they should have sufficient knowledge to be in position to be able to consider their responsibilities under the Health and Safety Act’.
As well as this there are more recent publications outlining requirements under both Queensland Government Code Of Practice for Work Environment Facilities to provide fresh air, quality air and thermal comfort. Which is a word for word cut and paste of the Australian federal government’s Safe Work Australia Code of Practice for Managing The Work Environment and Facilities.
The bottom line is you need fresh air coming into the building to be compliant coupled with a good service regime. On some sites is easier said than done. If you have access to clean fresh air and its coming in via mixing into your airconditioning or by other mechanical or even non-mechanical means, you are most likely across the line already. We have a Fluke Air meter here that I am willing to loan to safety professionals for a small donation to your nominated charity and all you need to do is measure the amount of carbon dioxide in the air and confirm that it is within acceptable exposure limits and if you are, then add it to your list of managed risks. If it’s not, then address it with your HVAC contractor and they will correct it. That’s the compliance side taken care of.
What about the positive health benefits for your people occupying these buildings?
Fresh air means respirable flu germs are diluted and often expelled from the building therefore less likely to spread. Trust me, im a ducter! It has been proven that people are more alert and productive when fresh air is introduced into buildings.
A well designed system with integrated fresh air should provide a slight positive pressure within the building envelope which should be just enough to also change the volume of air within the building over a period of time. Some larger commercial premises will purge the entire conditioned space of the building in the early hours of the morning when the temperature is at its coolest. This is done at this time for energy savings as well.
Then there are the filters, the filters are the office workers P.P.E. Filters can degrade very quickly with regular washing and lose their capacity to arrest dust or particulates. Filters also come in many different forms. We prefer gel coat filters which would generally be disposed of and replaced when they are loaded but they can’t be used in all locations. The value of what influence good filtration can have over the quality of air in any building is often overlooked and can’t be underestimated.
Here is a guide to particle sizing that needs to be considered with filter selection.
Metallurgical Dust – 0.5 – 100
Fine road dust – 5 to 20 micron
Dense smoke carbons and cigarette smoke – 0.01 to 1 micron
Bacteria – 0.8 to 10 microns
Pollens – 5 to 80 micron
Mould Spores – 3 to 15 microns
Viruses – 0.01 to .25 microns
I could go on for another hour about photocopiers and ozone, formaldehyde, volatile organic compounds in pre-fabricated buildings, mould, dirty ductwork but I will leave that for another day…