Originally published by Mitsubishi Electric, AACS Ltd are a Mitsubishi Electric Accredited Installer
Effective ventilation should be the starting point when looking to improve IAQ. Whether by natural or mechanical means, ventilation should remove stale and humid air whilst circulating fresh air from outside of the office.
Although opening windows is one way of achieving this, it is also uncontrollable and often leads to thermal discomfort. As reducing COVID-19 transmission is central to making offices fit for return, controlled ventilation which provides a constant supply of fresh air is a must.
Mechanical Ventilation is intended to provide the required steady stream of fresh air, ensuring all employees benefit from the removal of stale air, rather than those lucky enough to be sitting by an open window.
There are, however, recommendations from REVHA on how to operate mechanical ventilation systems to prevent spreading COVID-19. REVHA recommends that systems should not be switched off and should instead operate at a lower speed when the building is not in use. When employees can again return to the office, ventilation should operate at a nominal speed at least 2 hours before the building opens, and switch to a lower speed 2 hours after the building has closed. Central recirculation is not recommended due to the risk of recirculating contaminated air.
Mechanical Ventilation with Heat Recovery (MVHR) systems are able to deliver the required ventilation but do so in an energy efficient way, so that the energy used to heat the indoor air, isn’t just ‘thrown away’ when the fresh air is brought in. They can capture up to 80% of the heat energy from the outgoing air to bring the incoming air nearer to the desired temperature, meaning less energy is required to bring the fresh air to room temperature.
the HSE has stated that the risk of spreading Coronavirus via air conditioning is extremely low
Many modern air conditioning systems come fitted with powerful filtration which can filter out harmful airborne pollutants and pathogens. Not only will this improve the health of hay fever and asthma sufferers by removing allergens such as dust and pollen, but it will also minimise the risk of Sick Building Syndrome.
The more obvious benefit of air conditioning is the ability to remove humid air by providing a constant, cool temperature which boosts productivity and alertness.
Importantly, the HSE has stated that the risk of spreading Coronavirus via air conditioning is extremely low as long as there is an adequate supply of fresh air and ventilation.
there is arguably no better time to tackle the problem of poor IAQ inside our offices.
HEPA and Activated Carbon Air Filters
Air filters prevent certain particles and molecules from remaining in the air we breathe. HEPA filters, in particular, are excellent in protecting our health. By capturing dust and allergen particles as well as some VOCs, air purifiers equipped with HEPA filters can improve IAQ drastically.
However, there are many gaseous substances that HEPA filters cannot touch. In these cases, carbon activated air purifiers should be considered. Activated carbon air purifiers work by trapping harmful molecules on a bed of activated charcoal, eliminating them from the air.
These systems are extremely effective in filtering out numerous VOCs including gases given off by cleaning products, drying paint and cigarette smoke. It's important to note that carbon activated filters require replacing once they become saturated with pollutants.
Air Quality Monitoring
How do we know the quality of our indoor air unless we are continuously monitoring it?
To ensure our office HVAC systems are optimised, we need access to accurate information, such as the local temperature and humidity and levels of CO2 and pollutants.
From here we can adjust our buildings accordingly.
COVID-19 has forced us to take a better look at our indoor environments, and whether or not they're good for our health.
As we continue to work from home, there is arguably no better time to tackle the problem of poor IAQ inside our offices.
Because pandemic or not, protecting employees from harmful pollutants and airborne viruses whilst at work should be a given, and ensuring new or existing HVAC systems are optimised for long-term health is not only a good place to start, but is also necessary.
Read the original article here