Thermal comfort within ‘artificial environments,’ whether you are at work, at home or at leisure, plays a significant role in occupant health and well-being. This in turn has an impact on performance and productivity. In tandem with demands to reduce our carbon footprint, these factors are driving technological innovation in the way thermal comfort is delivered to building occupants.
The green building industry is focused on sustainability from two angles; reducing the impact of buildings on the environment, and reducing negative impact of buildings on their occupants. Sustainability rating tools such as Green Building Council of Australia’s “Green Star” scheme reflect these dual foci by awarding points for resource efficiency and indoor environmental quality (IEQ).
The overwhelming majority of green building research investment to date has been on the former – resource efficiency of buildings – but new research and technology in IEQ is changing that.
Staff costs, including salaries and benefits, typically account for about 90 per cent of business operating costs. Although the costs of ill health vary by sector and country, and are rarely comparable, research led by the World Green Building Council shows the impact is clear:
- The annual absenteeism rate in the US is three per cent per employee in the private sector, and four per cent in the public sector, costing employers $2,074 and $2,502 per employee per year respectively
- Poor mental health specifically costs UK employers £30 billion a year through lost production, recruitment and absence
- The aggregate cost to business of ill health and absenteeism in Australia is estimated at $7 billion per year, while the cost of ‘presenteeism’ (not fully functioning at work because of medical conditions) is estimated to be AU$26 billion.
Seminal research in 2003 identified 15 studies linking improved ventilation with up to 11 per cent gains in productivity as a result of increased outside air rates, dedicated delivery of fresh air to the workstation, and reduced levels of pollutants.
A meta-analysis in 2006 of 24 studies – including six office studies – found that poor air quality (and elevated temperatures) consistently lowered performance by up to 10 per cent, on measures such as typing speed and units output.
Similarly, in a 2011 lab test which mimicked an office, a range of office-related tasks were carried out with the presence of airborne VOCs. Increasing ventilation four-fold was found to improve performance by up to eight per cent.
CO2 levels are one way to measure air quality, and can occur as a result of poor ventilation. One recent lab-based study using simulated decision-making tasks showed CO2 having a significant detrimental impact (11 to 23 per cent worse) at 1,000 parts per million (ppm) compared to 600 ppm, despite 1,000 ppm being widely considered acceptable.
Improving thermal comfort to the satisfaction of everyone is a difficult business however.
According to the UK Health and Safety Executive (HSE), the best one can realistically hope to achieve is a thermal environment that satisfies the majority of people (around 80 to 85 per cent as an average) in the workplace, or put more simply, "reasonable comfort." By deduction, up to 20 per cent of occupants in an office could complain of “thermal discomfort.”
A 2006 survey by recruitment consultants Office Angels and the UK trade union USDAW found 15 per cent of workers have arguments over how hot or how cold the temperature should be; 81 per cent of workers find it difficult to concentrate if the office temperature is higher than the norm; and 62 per cent of workers state that, when they are too hot, they take up to 25 per cent longer than usual to complete a task.
Recently, Dr Richard de Dear of The University of Sydney offered the caveat that, “despite the large volume of research effort directed at it over the last couple of decades, our understanding of the thermal comfort effects on productivity is far from clear.”
But de Dear, a world-renowned expert in indoor climate and air quality who has been researching thermal comfort in buildings for the last 30 years, also adds that indoor environmental quality is just too important for companies to ignore today.
As part of its quest to measure and improve the indoor human comfort factor of office buildings the University of Sydney's Indoor Environmental Quality (IEQ) Lab has recently launched world-leading technology known as SAMBA. The new technology is the brainchild of PhD student Tom Parkinson, who developed the idea with his brother and IEQ research assistant Alex Parkinson over the past two years under de Dear's leadership.
SAMBA is designed to measure air temperate and speed, humidity, light, sound and air pollutants - the key factors shown to have the greatest impact on an office worker's health, comfort and productivity. The device is built on sensor technology that relays information about a building's indoor environment back to a central computer for further analysis.
"IEQ is a complex science,” said de Dear. “SAMBA will help to make sense of the science by giving companies the information or evidence to understand how efficiently and effectively their building is operating for the comfort of its people."
Multiple units are placed at various points throughout a building (as close as possible to occupants) and are continuously monitoring, allowing for real-time and in-depth reporting for building owners and facility managers. The low-cost sensors wirelessly feed real-time data to a dashboard monitored by a team of indoor environment quality experts at the University of Sydney for analysis and provide advice on how to optimise the building’s IEQ.
"Until now the industry has been limited by technology and high costs to capture this information through one device. What we now have is a revolution in technology, which has been produced at a relatively low cost and will have high returns for companies and its employees," said de Dear.
Ashak Nathwani, University of Sydney Lecturer in Mechanical Services and Facilities Management, noted that SAMBA measures humidity, temperature, noise, lighting, VOCs, CO2 levels and more.
“The old adage 'what can be measured can be managed' applies. Hence it can be used for diagnostic purposes whereby say if the CO2 levels are high then it means more outside (fresh) air needs to be introduced - generally via the air conditioning system,” Nathwani said.
“Similarly if the temperatures are consistently low in a specific floor or zone then the Building Management System (BMS) and/or the air conditioning system may need to be adjusted to correct the situation.”
As a result, Nathwani noted there could be energy savings. It can also be used to provide data for NABERS IEQ assessment in a cost effective way relative to current methods which are labour intensive.
SAMBA is offered as a research partnership to the property industry in three packages - Platinum ($35,000) which includes 15 SAMBAS, Gold ($25,000) which includes 10 and Silver ($15,000) which includes five. The partnership is valid for a year.
Regarding the cost of addressing IAQ issues, Nathwani said it all depends on a variety of factors.
“If the building is old and the maintenance of the HVAC and other building services is not being carried out efficiently then the costs to rectify IAQ issues could be very high. generally form my experience (having spent 35 years as an engineering consultant) the costs vary from $10 per square metre to $35 per square metre, obviously depending on the age, size and type of the building complex,” he said.
With testing so far indicating the accuracy and reliability of the sensors meets or exceeds industry standards, the new IEQ measurement technology is set to enable more accurate IEQ ratings and benchmarking within the property industry.
“SAMBA will help see IEQ ratings become as important as energy and sustainability ratings for building managers and owners in the near future,” Nathwani said.