While air-conditioned spaces offer welcome respite from the summer heat, multiple studies over the past decade have found the average person spends as much as 90 per cent of their lifetime indoors — and not just when temperatures rise.
“Emiratis may spend an even greater percentage of their time indoors because of high ambient temperatures and cultural factors that may limit outdoor activities,” says an Environment Agency — Abu Dhabi 2014 report.
Health concerns
But concerns are rising over the health impact of spending so much of our lives indoors. Sick building syndrome has seen an alarming uptick as a result of poor air quality management, ventilation and other factors. It is characterised by symptoms that develop when an individual is in a specific building, but not limited to a single definable illness. These typically improve or resolve after leaving the building. Symptoms include itchy dry eyes, runny nose, dry throat, chest congestion, cough, skin rashes, headaches, fatigue, dizziness and abnormalities in taste or smell.
Some building-related illnesses have a causative relationship with poor building conditions.
“Exposures that cause building-related symptoms and illnesses in non-industrial premises are wide ranging,” explains Dr Kirnesh Pandey, one of India’s leading diabetes and thyroid specialists and head of department at Bombay Hospital, Indore. He lists allergens such as mould, fungal spores and dust mite excreta; gases such as carbon monoxide and sulphur dioxide; organic compounds such as solvents, paints and printer emissions; cleaning chemicals such as ammonia; and a high density of particulate matter. “These are just some of the exposures even before we account for a host of viruses, bacteria, second-hand smoke and perfumes, just from having a large number of people packed into an airtight space.
“Building-related symptoms affect atopy, asthma and allergy-prone patients more than others. They are also at higher risk than normal of developing illnesses such as rhinitis, hypersensitivity pneumonitis and dermatitis. Legionnaires’ disease outbreaks can result from contaminated, poorly maintained AC systems.”
Ventilation matters
Suresh Balakrishnan, Joint Managing Director of Stulz-Chspl, says, “Ventilation is known to account for as much as 60 per cent of indoor air quality issues. Improper temperature management, air conditioning and inadequate exchange of treated fresh air in proportion to recirculated air contribute to an increased risk of several building-related symptoms and illnesses.” Stulz is a Germany-based precision cooling company that recently expanded to the industrial and commercial AC segments with a range of intelligent air-handling units, treated fresh air units, air purification units and underfloor air distribution systems.
Gary Reader, General Manager at ServeU, Union Properties’ facilities management firm, puts the build-up to poorly ventilated buildings in perspective: “During the 1970s, there were significant changes to the ventilation building design codes to build more airtight buildings. The design specifications were tightened, inadvertently reducing the ventilation capabilities of the building to 5cfm per person. As we know, there was a large boom in the UAE that saw the creation of a lot of high-rise residential and office-style buildings, mostly built to tight specifications to reduce cooling loss.”
The US Environmental Protection Agency Base Study 2013 observed that maintaining building temperatures at lower ranges in winter and higher in summer resulted in fewer building-related symptoms. Balakrishnan says, “The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recommends winter temperatures between 20 and 24 degrees Celsius and in summer from 22.5-27 degrees Celsius, depending on relative humidity.”
Older buildings
Public health departmental concerns about the rising incidences of sick building syndrome are relatively recent. This poses significant challenges in fixing older buildings that were built before ASHRAE revised design specs for ventilation around 2008. In this revision, tolerances were increased to tackle inherent problems of poor ventilation and high-volatile organic compound levels indoors. As a solution, retrofitting with more intelligent parts is often a viable option to meet new standards.
“Stulz has successfully retrofitted EC fans in premises where the rest of the HVAC system is in relatively good condition,” says Balakrishnan. “EC fans can be directly connected to any sensor with an appropriate range of performance input to provide closed loop control for temperature, pressure or any other required parameter to efficiently manage airflow. [They] are also significantly more energy efficient than those powered by AC motors, in addition to being more reliable with easy integration to the building management system.”
The question remains, however, that given living indoors in air-conditioned environments for the most part is now a fact of life, how does one prevent or mitigate building-related symptoms and illnesses? “It is advisable to look for obvious signs of dust or water damage in a building and make note of any uncharacteristic odours, stuffiness or being too hot or cold and alert the building management of any such, at the outset,” says Dr Pandey.
“Most building-related illnesses and symptoms are connected to multiple exposures combined with inadequate ventilation. Ultimately, without improvement in building conditions, it would be difficult to treat the patient in isolation, if they continue being exposed to these conditions.”