Keeping air safe from the inside out


28 March 2017
Steve Hope, from Guardian Water Treatment, explains the importance of air conditioning and ventilation maintenance in the fight against health risking Indoor Air Quality (IAQ).

I’m sure you’ve all read the headlines. Not a day goes by without yet another frightening statistic relating to air pollution, how bad it is and the effect it could have on our health. 
With the majority of people residing in the biggest cities, many of us risk our own wellbeing by where we live and work. When we step off the street, however, we should be entering a sanctuary of hygienic air that facilitates a happy and productive day, right?
The reality is often not quite so positive, with poorly maintained air handling and conditioning equipment meaning air is not properly filtered, pollutants are finding their way in, and bacteria is being given a place to thrive.
Steps to improving IAQ
In the first instance, it’s essential that appropriate air handling equipment is chosen for a building and that this is reviewed as layout changes or more people join a company. Often, we see an air conditioning scheme that is based on the historic design of an office, with no adjustments made when desks move, stud walls are added or additional members of staff are employed. What may have been fit for purpose initially, no longer provides an effective solution. Every time a building changes, so should its air conditioning and ventilation.
Once installed (or changed), as with all HVAC equipment, maintenance is essential. For example, there is a mad panic for air conditioning to be serviced once the weather warms up, but this is usually too little, too late and by this point, ac engineers are very busy, so building owners may be left with faulty equipment when they need it most – particularly at a time when the basic ventilation technique of ‘opening windows’ may not be advised if pollution levels continue to remain at dangerous levels.
A planned approach to maintenance is essential, based on individual product and its usage. While manufacturer’s instructions must of course be the bench mark, ideally, a maintenance programme should be tailored to the buildings – every environment is different and will put different strains on plant.
Part of this ‘fit for purpose’ maintenance comes from monitoring. By continually reviewing air quality and how equipment is working, small problems can be caught before they become big ones, with root causes addressed, rather than a make do and mend approach which could see knee jerk reactions such as ‘turning the ventilation up’, rather than understanding why the ventilation isn’t working sufficiently when it should be.
Important factors such as temperature and humidity levels, and pollutants; including carbon monoxide, dust, fungus, bacteria and pathogens; can be monitored on a regular basis to ensure the system is working efficiently. 
As well as controlling air quality, IAQ monitoring helps buildings to comply with Control of Substances Hazardous to Health (COSHH) Regulations. Regulation 7 (1) requires the employer prevent exposure and where this is not practicable, ensure that any exposure is adequately controlled. Without monitoring, employers are in the dark as to what substances their staff come into contact with.
IAQ investigation
If building occupants are complaining about air quality, then testing and assessment should be carried out to determine the source of the problem and address it. Carbon dioxide (CO2) testing is often performed during the early stages if an IAQ investigation - high levels are an indicator that there is not enough ‘fresh’ air being circulated. Without the removal of ‘spent’ air, odours and other contaminants can build-up.
HVAC equipment should be routinely inspected and associated ductwork cleaned, with factors such as airflow, temperature, humidity and pressure differentials tested in the different areas of a building.
The cost of poor IAQ
Apart from potentially having a negative effect on IAQ, a blind and unplanned approach to HVAC equipment will also lead to increased energy bills and maintenance costs. If equipment isn’t working properly because filters haven’t been cleaned, for example, it will strain harder to meet its required output, therefore using more power. Leaving plant to operate in this way will eventually lead to a shorter lifespan and breakdowns, costing more in the long run where replacements and out of service maintenance call outs are required. As the old adage goes ‘you have to speculate to accumulate’ – this is always true when it comes to the effective running of building services equipment.
This speculation shouldn’t just be viewed as a step to cutting mechanical costs, either. Statistics have proved that poor IAQ impacts productivity, leaving staff finding it hard to concentrate. Where health implications are severe, days off work may also ensue. Taking a short term view of air handling systems and their importance is therefore potentially costly on a number of levels.
Contaminant culprits
Contaminants may originate from inside and outside of a building, potentially containing airborne chemicals. What comes from outside should be stopped by air handling equipment, which is why keeping filters in good working order is so important.
If a work place produces excessive amounts of potential irritants than a building’s ventilation systems should be adjusted to suit. It’s important that flow rates are kept in check – if more air is removed from the building than is supplied, negative pressure can build-up, causing unconditioned air to flow in through gaps. Boilers, water heaters and other combustion sources must all be properly ventilated.
Staff education is also key – air ventilation grilles can get blocked because people perceive them as ‘draughty’, they must also be trained to use thermostats properly. Ideally, each area should have zoned temperature control so individuals can feel comfortable in their space.
With the cost of poor IAQ potentially a high one, effecting staff health and productivity, and the efficient running of associated plant, cutting corners is a false economy that no business can afford. Let’s make sure that once we’re inside, at least, the air we breathe is safe.
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