Karen Fletcher looks at the challenges of ventilating our indoor spaces to deliver safe havens

Poor air quality is a public health issue across the UK.

You might even say that it’s even more insidious than a global virus because its effects are not so immediate (for most people), and it has been relatively overlooked for many years.

But the health effects are very real and have a direct long-term impact on the NHS in terms of preventable diseases such as lung cancer, heart attacks and strokes.

As recently as the 14th of January 2022, Londoners were told to avoid ‘strenuous outdoor physical activity’ because of high levels of air pollution.

It wasn’t a great way to welcome in the new year, but it sets the tone for what could be an ongoing problem for the whole of the UK.

The technology exists to create buildings as safe havens for air quality

Karen Fletcher Karen Fletcher Content director of Rocket Content

Invisible danger

London’s hazardous air quality was due to a persistent area of low pressure over Western Europe. As a result, pollution built up in the city, creating a largely invisible pall of dangerous particulate matter (PM 2.5) which was 6.5 times higher than annual quality guidelines set by the World Health Organisation (WHO).

Sources of pollution include vehicle exhausts, log burners, construction work and even cooking. PM 2.5 particles are only 2.5 microns in size – a human hair is around 50 microns wide.  

At that scale, they can enter the human body and impact crucial organs including the lungs and heart.

Perhaps one of the few positive outcomes of the past couple of years is that the public and government have become far more aware of what’s in the air they breathe.

While the focus is on virus mitigation, here is a growing understanding that good IAQ makes a significant difference to human health.

Raising awareness and standards

Building services professionals will already be aware of this.

BESA has been working with Mitsubishi Electric on a ‘Buildings as Safe Havens’ campaign to raise awareness of the issue – and has been lobbying government to legislate for higher standards.  

The updated Building Regulations Part F (coming into force from June 2022) introduce new rules on ventilation in homes and commercial buildings.

One of the challenges for engineers is that while IAQ requires ventilation, that has implications for energy use in homes and non-dwellings. Building services must find a balance between good indoor air quality and energy efficiency.

And another thing!

What’s more, making ‘safe havens’ of our offices and homes goes beyond energy and IAQ.

There are factors such as overheating (now covered in Part O of the Building Regulations) as well as noise (a major factor for city dwellers).

As ever, it’s a case of identifying and applying the right technologies to meet all these requirements.

For example, Part F points to mechanical ventilation with heat recovery (MVHR) can be used in homes and non-dwellings to reduce heat loss from ventilation even in colder months.

It can also reduce the need for open windows in buildings near busy roads – keeping both pollution and noise at bay.

There isn’t a lot of point telling people to stay indoors to avoid pollution if the air inside isn’t filtered.

The technology is there to alleviate the problem, and to create safe havens of good IAQ in homes and workplaces.

Karen Fletcher is former editor of Modern Building Services and CIBSE Journal