Is your building making you sick?

There is a tendency to blame most of the illnesses today on your air conditioning and the much touted sick building syndrome (SBS). A World Health Organization report as far back as 1984 suggested that up to 30 per cent of new and remodelled buildings worldwide may be linked to symptoms of SBS, which in turn is related to indoor air quality (IAQ).

"SBS results from poorly ventilated buildings with insufficient fresh air," told GN Focus Mick Dalton, Managing Director at Musanadah FM, a subsidiary of Khalid Alturki group, a Saudi Arabia-based investment and development company. "Physical symptoms include headache, coughing, dizziness, a burning throat, fatigue and the inability to concentrate. But first visit your doctor to rule out a medical condition. Talk with others in the building to see if they are experiencing similar symptoms. Air conditioning is not the only cause of SBS. Also talk to your facilities management who can easily identify if the building is sick after a detailed investigation," he added.

Local presence
So does the syndrome exist in the UAE? "I have come across two cases," said Dalton. "We solved the problem with good ventilation and by educating the maid on how to properly clean the floor."

Sick Building Syndrome was prevalent in the 90s, said George Berbari, CEO at DC Pro Engineering, a leading authority in the field of district cooling engineering.

"We had to do some major rectifications in buildings during that period, where lack of introduction of treated and dehumidified fresh air, indoor units oversizing and poor control of supplied chilled water temperature have collaborated with dramatic results in buildings, where UAE has one of the highest absolute humidity in the world. Today, the designs are much better with some exceptions," said Berbari.

Humidity-related issues
"In the 90s, we also started seeing issues of mildew and fungus in buildings, which arose due to factors such as humidity exceeding 70 per cent, dark spots in the buildings and organic material that fungus can feed on, and affected not just human health but also indoor living quality by damaging interiors. But consultants, manufacturers and contractors started giving attention to humidity control within the UAE and building health has improved tremendously since then," said Berbari. "Still, one can see that quite a few buildings are badly designed and need to improve their humidity controls."

Air conditioning impacts humidity control. Berbari advises consultants and designers to control humidity within buildings by controlling the chilled water supply temperature (between 5°C to 7°C), properly sizing fresh air and exhaust quantity in line with international standards and avoid indoor units oversizing in excess of 30 per cent.

"But then we see that consultants are specifying too much of fresh air in buildings, sometimes as much as double of what the international standards specify, without balancing it with exhaust specifications (sometimes up to a 50 per cent difference, when you need just a 10 per cent higher proportion of fresh air to exhaust)," he said. He also advises that indoor air temperature should be ideally be around 23°C or 24°C and air conditioning should be run on low speeds for best results for humidity control.

"There is a tendency to over cool buildings. I also met a client who had a misconception that malls and supermarkets should have a shopping temperature at 18°C," said Berbari. "But this causes a great deal of discomfort to shoppers."

In the end, it is all about creating comfortable living and working environments. A simple few precautions and answers lie just a switch away.

"Inadequate ventilation, which may also occur if heating, ventilating, and air conditioning (HVAC) systems do not effectively distribute air to people in the building, is thought to be an important factor in SBS," said Dalton.

Acceptable IAQ
In an effort to achieve acceptable IAQ while minimising energy consumption, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recently revised its ventilation standard to provide a minimum of 15 cubic foot per minute (cfm) of outdoor air per person (20cfm/person in office spaces). Up to 60cfm/person may be required in some spaces, such as smoking lounges, depending on the activities that normally occur in that space (ASHRAE Standard 62-1989).

"Other SBS causes include chemical contaminants from indoor and outdoor sources and biological contaminants — bacteria (legionella), moulds, pollen and viruses. These elements may act in combination, and may supplement other complaints such as inadequate temperature, humidity or lighting. HVAC systems should be designed, at a minimum, to meet ventilation standards in local building codes.

However, many systems are not operated or maintained to ensure that these design ventilation rates are provided," said Dalton, quoting research findings from ASHRAE and Building Owners and Managers Association (BOMA) International.

"To combat the legionella bacteria, which grows in water, one must ensure proper water treatments for cooling towers on building roofs and place them away from fresh air handling units, added Berbari.

"Also, let your taps run for ten minutes and stand away from the bathroom when back from vacations and wash your showers heads in chlorine solution once a month," he advised. Air conditioning certainly acts as a catalyst to spread this illness, but is definitely not the main factor.

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How to make your air conditioner work in your favour

People in excellent health can also suffer on account of excessive heat, cold and reactions caused by pollen, bacteria, virus as well as invisible airborne particles. By improving IAQ, conditions such as fatigue, headaches, colds, discomfort, coughing, allergies and dehydration can be alleviated. An air-conditioned environment prevents growth and spread of germs and microscopic particles, and it has proven to be the most effective air-purification technology that guarantees a contamination-free indoor environment.

Leading AC manufacturers offer products that come with a whole range of innovative technologies such as air filtration, sterilisation and humidification that remove harmful particles, eliminate foul odour and balance the moisture in the air. Constant evolution of such technologies has gone a long way in benefiting health. More and more products are combining latest in technology to grab a portion of the consumer pie.

However, only proper usage of technology and regular maintenance will help AC users stay away from illnesses. AC ducts are not cleaned regularly by most owners despite knowing the importance of cleaning. Air conditioners are a very common source of colonisation by moulds and fungus. If the situation is not corrected in its early stages, it can lead to health issues. Periodical and complete cleaning of filters and ducts is an important preventive activity.

— Jogiraj Sikidar