Hern Yau, Product Manager at Mitsubishi Electric
The impact of poor indoor air quality on health has been a hidden issue for many years. Now, the COVID-19 pandemic has put it firmly on the agenda.
This increased awareness of the correlation between health and the air we breathe is evident from government level discussions about the role of ventilation in reducing the transmission of diseases.
Both the British Medical Association (BMA) and the UK’s chief scientific officer Sir Patrick Vallance called upon the government during the pandemic to implement higher standards for building ventilation and indoor air quality, to help the country to navigate its post pandemic future.
This is the time for concerns about indoor air quality to be properly addressed and tackled, and for higher standards to be set for the long-term. As a result of increased demand for improved indoor ventilation rates, the stakes have been raised for air filtration and mechanical ventilation.
Though a focus on preventing infection and disease is important, a change in the approach towards air quality standards needs to prioritise the health and wellbeing of occupants at a wider level.
Buildings should act as ‘safe havens’ away from both outdoor and indoor airborne dangers, allowing occupants to have a more productive, more comfortable and healthier experience in buildings for years to come.
Air pollution – A major health issue
COVID-19 is not the only illness linked to indoor quality, and these kinds of conditions will continue to be a problem long after the pandemic. The UK is now facing an air pollution triggered health crisis, with the issue causing between 28,000 and 36,000 deaths per year.
These harmful pollutants include nitrogen dioxide (NO2), arising mainly from petrol and diesel engines, and sulphur dioxide (SO2), released when coal is burned for fuel in power station.
However, some of the most dangerous pollutants take the form of particulate matter (PM), tiny particles made up of a mixture of solids and liquids present in the air. PM can be created in many ways, including friction from car brakes, dust from roads and construction work.
A common misconception about pollutants is that they are all created by outside means, such as coal plants and traffic, when in fact there are numerous chemicals and substances inside our living and working spaces that can have a detrimental impact on health.
Carbon dioxide caused by respiration can build up in poorly ventilated spaces, leaving our homes, schools and offices filled with this harmful gas.
There are also volatile organic compounds (VOCs) which cover various chemicals found indoors, such as cleaning products, scented candles, aerosol sprays, and the toners used in photocopiers.
Excess humidity is yet another issue that can be detrimental to health. Damp conditions caused by poor heating and ventilation, often produced by drying clothes in unventilated spaces, can lead to mould – which is widely recognised as detrimental to lung health.
Some dust, viruses and bacteria fall into the smallest category of particulate matter, PM1, which can penetrate deep inside the human body and cause severe damage.
After two years of COVID-19, tackling PM1 is a growing concern when managing the health and wellbeing of building occupants.
Putting ventilation first
Back in 2019, the Building Engineering Services Association (BESA) called for buildings to be ‘safe havens’ to protect occupants from the worst impacts of air pollution, raising awareness of the importance of good air quality.
More recently, a report commissioned by Sir Patrick Vallance and published by the National Engineering Policy Centre (NEPC) exposed widespread neglect of ventilation prior to the pandemic, highlighting the importance of building ventilation in reducing the transmission of COVID-19 and other infections.
The pandemic revealed flaws in the design, management and operation of buildings – including the implementation of effective ventilation systems.
An article for the journal Science from a group of 40 leading scientists and academics from around the world called for a “paradigm shift” in how buildings are ventilated after noting how the legislation involved in the prevention of airborne pathogens was being “addressed fairly weakly”.
Advocating for the introduction of an air quality certification system for public buildings, the group estimated that the installation of ventilation and filtration systems able to remove airborne pathogens would add just 1% to the construction costs of a typical building.
Fortunately, there is a growing indication that ventilation is being given greater importance in building legislation.
For example, Part L and Part F of the Building Regulations now contain ventilation guidance on non-domestic buildings and existing homes, stating that adequate ventilation should be provided in order to maintain a high level of indoor air quality.
The way we design, manage and operate our buildings is changing due to new regulations and COVID-19 guidance, but if they are to become ‘safe havens’ for their occupants, ventilation must be given greater priority.
Taking energy use into consideration
Ventilation is key to achieving good indoor air quality, but its use must take into consideration factors such as building energy use and occupant comfort.
Introducing air that is too cold or too warm can adversely impact both occupant wellbeing and performance, as well as overall energy efficiency, so monitoring the energy required to heat or cool incoming air is essential for maintaining comfort and productivity.
Using mechanical ventilation with heat recovering (MVHR) systems is one way to reduce energy use when ventilating. This valuable technology can transfer up to 90% of the energy from outgoing stale air to heat incoming fresh air, meaning less energy is needed to heat the building compared to non-heat recovering ventilation systems. These systems can also deliver a slow but constant movement of air throughout a building, unlike natural ventilation.
To achieve the best results, buildings must select an appropriate level of filtration. For example, class ePM1 filters can reduce particulate matter down to PM1, making it an excellent choice for ventilation systems in buildings close to busy roads or in city centres.
Another option to consider is the monitoring of indoor air quality. Indoor air quality tracking schemes and equipment can be expensive, however there are cheaper monitors available on the market. When using any monitor, it is important to check that it is a calibrated instrument backed by support for interpreting results.
Monitoring for CO2 levels is useful for judging the effectiveness of fresh air systems in occupied spaces, with CO2 monitors able to show the level of fresh air being delivered to the space. This helps lower energy use, as the system can be increased or reduced depending on the occupancy of the room.
A redefined approach
Approaching the design of new buildings with health and wellbeing in mind means taking into consideration the benefits that good indoor air quality can bring to productivity and general comfort – in line with BESA’s ‘safe haven’ goal in 2019.
Head of technical at BESA, Graeme Fox has said: “Sustainability is not just about carbon and energy saving; it is also about ensuring that the facilities we build and refurbish can sustain human activity in the long-term while also safeguarding health, wellbeing and productivity.”
Bringing good air quality to our homes, schools and workspaces goes beyond just keeping occupants safe from viruses and pollutants. Improving the quality of our air supports both physical and mental health, creating more productive environments and working towards a healthier way of working.
Hern Yau is Product Manager at Mitsubishi Electric
About Mitsubishi Electric
Originally founded in 1921, the company known today as Mitsubishi Electric has almost 100 years of experience in providing reliable, high quality products and support to installers, specifiers, corporate clients and general consumers all over the world.