The importance of Indoor Air Quality (IAQ) has come to the fore of the real estate industry as it’s being recognised as a critical element in fighting the spread of COVID-19 in buildings.
As people spend the majority of their time indoors, it doesn’t come as a surprise that the quality of the air in close quarters – and the systems used to manage the airflow, to filter and purify the air – is a driver of people’s health in buildings in normal circumstances, but more so now.
As little as we still know about this virus, what has been cleared is that the diffusion occurs through respiratory droplets and fomite. However, there seems to be enough reason to believe COVID-19 may also be airborne (CDC; Public Health England; ASHRAE), opening up even more questions on how to manage efficiently and effectively indoor air quality to prevent the spread.
This understanding makes it vital for property managers to gain the right insight on the air in a building and adequately respond to the pathogens that may enter it. We know HVAC (i.e. heating, ventilation & air conditioning) systems are a starting point, but there is much to be said about the monitoring and effective control of these systems to ‘cleanse’ the air throughout the building – and the different needs the distinct spaces may have.
So, how do pathogens diffuse in close environments and what strategy can be approached to make the office building a safer place to be?
What we know about the ways COVID-19 spreads in closed environments
According to the Centers for Diseases Control and Prevention (CDC) and Public Health England, the infection caused by SARS-CoV-2 known as COVID-19, can be transmitted in multiple ways:
- Person-to-person: respiratory droplets
Person to person is thought to be the primary means of the virus transmission, happening when people are in close contact one to another, at a distance of 2mt/6ft. The spread comes via respiratory droplets produced when an infected person coughs, sneezes, shouts, talks or sings, therefore, landing in the respiratory tracts of nearby people.
- Person-to-surface: fomite
There is also the possibility that COVID-19 can be transmitted by touching a surface or object which has come into contact with someone infected. As the virus can live on inanimate objects for hours after the first contact, someone who touches it and subsequently touches their own mouth, nose, or eyes could get infected.
Another hypothesis sees the virus being spread via airborne particles.
- Airborne exposure
Even if research is still being conducted to confirm or deny this, at this stage transmission via air is a sufficiently likely possibility, as reported by the ASHRAE, to deserve attention when looking at means to control the diffusion.
What do these mean when looking at Indoor Air Quality?
As various studies have identified, Indoor Air Quality is a critical aspect which affects the wellbeing and productivity of individuals in buildings.
To quantify air quality, we need to look at the concentration of pollutants present in the enclosed environment. These are micro-particles and gases released by a number of materials such as the same building materials, appliances and office machines, and quite a few others (to know more, read our Healthy Buildings: Indoor Air Quality & the IEQ Framework).
To understand the reason why IAQ – and more generally the Indoor Environmental Quality (IEQ) of buildings – is so critical, the definition of IEQ by the Centers for Diseases Control and Prevention comes to help: “[IEQ is] the quality of a building’s environment in relation to the health and wellbeing of those who occupy space within it. IEQ is determined by many factors, including lighting, air quality, and damp conditions.”
It is through the ventilation system and airflow patterns in a space that people can be adversely exposed to the pathogens present in the environment, thus spreading it from person to person. Notably, small aerosols of less than 5μm can stay airborne for many hours after being generated, and travel through the space via the ventilation system (The Lancet, Respiratory Medicine).
What are the ventilation strategies that positively affect Indoor Air Quality?
The heating, ventilation and air conditioning system (HVAC) is responsible for providing the right air, temperature and humidity conditions in the workplace.
Implementing effective ventilation and air-cleaning strategies on the HVAC units may have the effect of purifying indoor air and provide better control over a possible disease transmission.
ASHRAE, for example, states valid airflow patterns – and dilution of room air – can help remove infectious agents. Applying particle filtration to reduce their transportation from one ambient to another is another good solution. Temperature and relative humidity, too, can be cause for contamination if not properly managed, with appropriate relative humidity believed to be between 40% and 60%.
But how can a property manager respond to COVID-19 in practice? To this date, most agencies such as the REVHA and CDC have suggested:
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- An increased ventilation
- An increased outdoor air ventilation
- To close recirculation dampers
- The use of MERV-13 (or the highest compatible) filters, and seal edges of the filter to limit bypass
- Keep systems running longer hours, 24/7 if possible, to enhance air exchanges in the building space
Cost-effective management of Indoor Air Quality is via IoT & Smart Sensors
The HVAC system of an office building is normally controlled by the Building Management System (BMS). However, what a BMS doesn’t offer is an integrated solution to bring all the different building systems under a single ‘tool’.
A smart building platform, which relies on IoT technology, takes this further step by becoming a nodal point for all the systems and provides the visualisation and insight needed to make informed decisions. Without the need for hard-wiring and using the existing networks (if not too obsolete), the integrated operating system becomes a cost-effective solution to 360° control over the building systems.
An effective smart operating system supports facility managers assess, regulate and maintain high standards of indoor air quality. It does this by providing an end-to-end view – at a floor and room level – and full remote control over the HVAC system, including real-time operating, maintenance and engineering actioning.
The IoT platform collates the data from the HVAC and the cloud-connected smart IAQ sensors so that facility managers can analyse and monitor the levels of airborne particulate concentration in the workplace, as well as control the ventilation, temperature and humidity in the building.
Facility managers can benefit from analysis of historical trends, too, for a comprehensive view and support to their audits needs.
Bipolar Ionisation Systems: Do we finally have a solution to defeat SARS-CoV-2?
Concerns for the possibility of aerosol particles dispersion in the environment – and the need to find an effective solution to the potential harm coming from the ventilation systems circulating infected air – has brought the attention of researchers on bipolar ionisation systems.
Ions are electrically charged particles usually present in nature.
Through ionisation, an atom or a molecule acquires a negative or positive charge by gaining or losing electrons, often in conjunction with other chemical changes. The resulting electrically charged atom or molecule is called an ion. (def. Wikipedia)
Indoor air quality sensors provide invaluable help to identify and manage compounds present in the air which can become harmful to the human body, as well as verify that the air is being replaced with fresh air. For example, sensors can analyse indoor levels of CO2, VOCs, Particulate PM 0.5 and PM 2.5.
However, bipolar ionisation systems provide even more assurance as they have been found to reduce infectious pathogens by more than 90%.
From mould to viruses, dust to bacteria, bipolar ionisation technology – applied to the existing HVAC system – releases ions into the airflow.
The charged ions introduced in the airstream attack the airborne pathogens changing their structure, so that it is easier for filters to catch them, and consequently neutralise them.
Research on some of these easily installed, low-maintenance and energy-efficient systems, has found that the technology could potentially neutralise SARS-CoV-2 in about 30 minutes.
Making your workplaces safe with a Smart Building Operating System
Smart Spaces is a smart building operating system, and community-first engagement app, which supports clients provide their occupiers with a safe and healthy workplace, ready for the future.
Our integrated platform enables buildings – making them smart – and helps property managers control and effectively execute remote maintenance of all the systems, in just one solution.
Get in touch with us to discover how we are de-risking the return to work.
