29 June 2020

Air pollution is one of the world's most dangerous health risks and scientists are now investigating possible connections between exposure to air pollution and vulnerability to the COVID-19 virus. Research shows that 80 per cent of deaths across four countries were in the most heavily polluted regions.

Speaking to The Guardian, Yaron Ogen, at Martin Luther University Halle-Wittenberg in Germany, said “Poisoning our environment means poisoning our own body, and when it experiences chronic respiratory stress its ability to defend itself from infections is limited.”

When we talk about air pollution we generally think of the air outside, but with people spending an unprecedented amount of time indoors, there has never been a more fitting juncture to consider the relationship between health and indoor air quality (IAQ).

A 2019 study by the Clean Air Day Campaign revealed that ultrafine particle pollution is on average 3.5 times higher inside the home than outside.

As we look set to be spending more time at home in the immediate future, improving indoor air quality and educating people about the risks are crucial public health considerations.

IAQ pre-Covid-19: the facts

Indoor air quality (IAQ) is determined by a number of factors from the presence of particles and polluting gases to providing adequate ventilation to pollution from the air outside. IAQ is affected by:

  • Gases, such as carbon monoxide, ozone and radon
  • Volatile organic compounds (VOCs)
  • Particulate matter (PM) and fibres
  • Organic and inorganic contaminants
  • Biological particles such as bacteria, fungi, and pollen

We know that each of these can have a considerable impact on health and well-being.

Before Covid-19 hit, there was a dogged determination to address issues such as energy efficiency and insulation of homes, but attention to ventilation and IAQ hadnt been given the same priority.

It is now apparent that astounding levels of pollution are being caused by everyday activities, such as ironing, washing clothes and cleaning. Fine dust particles and the presence of VOCs (found in many everyday household materials) are being linked to serious health conditions, such as allergies, eczema, asthma, respiratory illness, dementia, mental health problems, cognitive impairment and cancer.

One study by Zehnder found that the use of bleach when cleaning raises the levels of VOCs in the house by up to 25,623%! VOCs are also widely present in other cleaning products: air fresheners, aerosols and health and beauty products. Another Zehnder study found alarming pollution levels caused by cooking an omelette. The more time people spend indoors without adequate ventilation, the more likely they are being over-exposed to dangerous chemicals.

The impact of Covid-19 on lifestyle and work

We have spent more time in our homes during the lockdown, and this is likely to continue even as restrictions start to ease. Even prior to Covid-19, remote working was becoming more acceptable. Covid-19 has accelerated this trend. Not everyone will be going back to the office as usual.

Our homes have become our sanctuary and our workplaces. The Covid-19 lockdown may be giving us bluer skies and less smog, but could our homes be inadvertently posing a threat to our health?

That may well be the case, and here’s why. There are more people in the home at all times. More time indoors means increased use of appliances, increased CO2 from breathing and more moisture in the air. We are using more cleaning products, paints, varnishes and other DIY products. But people aren’t paying attention to improving ventilation to counter this.

The impact this is having on IAQ is significant and it will be compounded in the summer months when temperatures heat up. You can read more about overheating in homes and why architects must play their part in addressing risks in our previous blog posts.

Ventilation regulations must be reviewed

There is now even greater pressure on policy makers, architects, building consultants and building engineers to address the challenges involved in improving IAQ. Regulations in recent years have slowly started to acknowledge the need to do more to protect the quality of air indoors, but in the post-Covid world, more will need to be done.

Lets have a quick recap of the current regulations around ventilation.

Approved Document F of Building Regulations provides guidance on building ventilation. Essentially this states that in a domestic property, ventilation must be circulated continuously throughout the whole building. Extract ventilation must be used within an area of increased humidity or pollution, and purge ventilation must be possible in certain areas (the ability to open a window to air a room out).

In support of Approved Document F, the Governments Domestic Ventilation Compliance Guide (2011) gives detailed guidance on installation, inspection, testing, commissioning and provision of information when installing ventilation systems into new and existing dwellings.

The Chartered Institution of Building Services Engineers (CIBSE) developed and published TM59, a design methodology for the assessment of overheating risk in homes, in 2017.

It addresses the complex way buildings respond to external temperatures and presents a standardised methodology to assess overheating risk. This came about because there were no specific industry criteria to assess overheating in homes. With consultants likely to use different model set ups there was no real benchmark on which to base results.

Moving forward, improved performance of ventilation products is essential and will need to be looked at as TM59 protocol is further developed.

For new property development, IAQ and overheating must be addressed at the planning and design stages.