Safe air in a post-COVID built environment
Tuesday 11th August 2020
COVID-19 is making healthy buildings mainstream.
Whether you are confronting the impacts of indoor surroundings at home, or returning back to work, COVID-19 has highlighted the need for healthy buildings to #BuildBackBetter.
The World Green Building Council’s (WorldGBC’s) global project, Better Places for People, is opening a discussion with our partners to share insights on how the built environment can prevent the spread of COVID-19 without costing the climate.
Harvard University found long-term exposure to air pollution is associated with an 8% increase in the COVID-19 death rate. And we know 9 out of 10 people around the world already breathe polluted air.
At WorldGBC, we believe the role of monitoring must be emphasised when tackling airborne pollution: we cannot improve what we cannot measure. Through our Plant a Sensor global programme, we work with organisations across the world to install indoor and outdoor air quality monitors and report real-time data through a public platform, therefore increasing access to vital information for decision makers and designers worldwide.
As industry looks to reduce the risk of airborne disease particles as well as exposure to pollution, WorldGBC firmly advocates for ventilation, indoor air quality and various internal systems focused on occupant comfort to be key areas of this conversation.
However, in many parts of the world, increased ventilation and fresh air demand is linked to higher energy use.
So, how do we balance the elevated need for buildings that help control the transmission of infectious disease indoors—whilst minimising environmental impacts and working towards our climate goals?
How does the built environment balance ventilation requirements to improve indoor air quality, whilst working towards ambitious net zero carbon building targets by 2030?
Here we turn to our Better Places for People global partners to shed light on these questions through their technical expertise, ideas, and practical solutions for the industry.
What do building occupiers need to consider to maintain occupant health and wellbeing, particularly related to indoor air quality, as we start to repopulate our buildings?
Josh Jacobs, Director Environmental Codes and Standards, UL
The COVID-19 outbreak has left buildings of all kinds dormant for a period of weeks or even months. As communities and economies return to operations, it’s important to remember that there’s more to reoccupying buildings than simply opening the doors and turning the lights on. Based on months of impact, there are many aspects of building maintenance that need to be considered as well as operational adjustments to safely accommodate occupants under the new rules of engagement.
After over 200 building re-occupancy inspections over the past few months, we’ve discovered some common steps to take to help prepare buildings to welcome occupants again as safely as possible. We have also seen some issues that often go overlooked when buildings are sitting unoccupied.
Water systems need to be evaluated for the development of Legionella and other bacterial growth before they begin running again. HVAC and maintenance systems should also be inspected to ensure indoor air quality has not deteriorated as the systems were not being utilised. And a commonly overlooked factor that contributes to poor IAQ is products used in building hygiene. While the focus right now should be on the effectiveness of cleaning products, considering the chemical emissions that can occur is critical to maintaining healthy IAQ for a building’s occupants.
UL recommends reviewing the EPA’s list of environmentally preferred cleaning products, and reaching out to trusted professionals to make sure your building occupants will be as safe as possible when reoccupying facilities.
With the balance of fresh air ventilation and energy consumption during operation still a major concern, UL recommends reviewing the EPA’s list of environmentally preferred cleaning products and reaching out to trusted professionals to make sure your building occupants will be as safe as possible when reoccupying facilities.
What are some of the main considerations to promote health and wellbeing in an indoor air environment?
Jean-Marie Thouvenin, Director Building Physics, Saint-Gobain
Through its Multi Confort Sustainable Buildings programme, Saint-Gobain has been exploring many different aspects of building design to understand how comfort works in real built environments. There are a few concepts Saint-Gobain could bring into the equation applying multi comfort principles to office spaces in the post-COVID period.
Energy-efficient envelope and adaptive thermal comfort
Through its overall shape, orientation, number and size of windows and the ability of surfaces to reflect heat, the building envelope can control how much heat from the sun (solar gain) is allowed to enter into the building. Insulating the building envelope and using thermally efficient windows reduces heat loss in winter and conduction heat gains in summer. In such buildings, the absence of draughts, the stable walls and windows surface temperature and improved humidity control could enable setting the air temperature to a higher value in summer, or lower in winter, compensating the energy need for more ventilation, without reaching thermal discomfort conditions.
Air flow control
Good design, proper ventilation (mechanical and natural ventilation) and specification of the right building materials are essential to increase the supply of fresh air in a building, and to reduce our exposure to indoor pollutants and odours (see also Arch Daily on IAQ) in office spaces, a combination of acoustic and glass shields can enable “cubicle safety” from bio-aerosols while providing daylighting, views and connectivity to colleagues, and preserving acoustic comfort. Shield surfaces can be given antiviral, easy-to-clean and anti-aging functions. In such spaces, the need for more ventilation may be reduced.
Speech intensity reduction
Acoustic environments that are well balanced can block unwanted, harmful noise and enhance sounds that we want, and indeed need, to hear. Quiet buildings with good noise absorption also enable people to speak softer thus reducing the bio-aerosols emissions. This can be obtained with a combination of acoustic ceiling, wall panels or partitions. In such spaces too, the need for more ventilation may be reduced.
How can these strategies be achieved whilst also maintaining efficient use of energy and what is the role of smart technologies to meet these goals?
Agustin Garcia del Castillo Calvo, Sustainability Manager, Siemens
Can buildings really help in the battle against the current coronavirus crisis to better protect people who use the premises by using building equipment and systems like HVAC and Building Management Systems? At Siemens, we believe that they can.
The main precaution and safety measures firmly rely on each individual by way of social distancing, washing hands, and following all the rules and recommendations specified by local governments and health authorities. However, buildings, when operated and monitored correctly, can further support individual efforts.
Although many commercial buildings are currently “closed”, there are still a lot of facilities that must be kept working, regardless of or especially because of this crisis.
Many of these buildings run at least on average or above average capacity with a high number of occupants, while there are also buildings that are fully operational but almost empty.
Using HVAC and other Building Management System functions, these buildings must be operated in the best possible way. And the best possible starts with transparency, and to be able to measure and put the right data in place, especially with the main key performance indicators (KPIs): Air quality (CO2, Dust, Humidity) but as well equipment performance data. Additionally, these “closed” buildings cannot be left without attention. Despite being a second priority, they need accurate control and monitoring. This ensures that they are healthy and safe places to return to after the crisis – and that assets are protected while empty.
A smart building is a building that reacts, adjusting its set up points and requirements to specific situations. If the occupancy is reduced, the need for ventilation to keep in line with air quality standards will also be reduced, as it also will for energy consumption. So, measures to keep air quality at the highest standards have to be adapted to the building occupancy, access control and optimised energy consumption.
For that, and to keep fulfilling the sustainability commitments of the companies regarding CO2 emissions and carbon neutrality, even in COVID-19times, solutions like renewable energies, energy storage, Electric Vehicle charging infrastructure and the software that manages and predicts peaks, loads and energy sources are gaining a lot of importance.
The proposals of Siemens are based on recommendations of renowned industry associations (REHVA and ASHRAE) as well as on our own Siemens HVAC industry experience.
Key takeaways from this conversation:
As WorldGBCpartners have demonstrated above, there are a huge range of factors that can influence indoor air quality, and therefore potentially heighten the risk of infectious disease transmission. However, there are energy conscious ways of managing health risk without jeopardising our sustainability and net zero carbon goals.
There is clearly no 'one size fits all' answer, but a clever mixture of passive design interventions, incorporating energy efficient technologies, and adapting user behaviours are the fundamental components to be developed in each project.
We hope you have been inspired by these reflections from the voices of trusted experts, which widely support the work and leadership of our member Green Building Councils and their healthy buildings initiatives.
For more information on WorldGBC’s latest work to tackle pollution in the built environment, visit worldgbc.org/clean-air-buildings
About the WorldGBC:
The World Green Building Council global network catalyses the uptake of sustainable buildings for everyone, everywhere.
Transforming the building and construction sector across three strategic areas—climate action, health & wellbeing, and resources & circularity—we are a global action network comprised of around 70 Green Building Councils (GBCs) worldwide.
Find out more at worldgbc.org