You are what you breathe.


Is outdoor air quality more important than indoor?

Taken from Exploare Issue 4, the X Files is an open debate between two experts: one believer, one sceptic. Together, they discuss pressing topics that impact both our lives and industry.






Outdoor air pollution has been linked to cancer, asthma, cardiovascular disease, diabetes, obesity, and dementia. With approximately 40,000 deaths estimated to be attributable to outdoor air pollution in the UK annually, it’s a serious matter that can’t be ignored.

So what’s causing it? In urban areas, outdoor air pollutants are mainly emitted from on-road and off-road vehicles, but there are also contributions from power generation, incinerators, and industrial process, depending on the locations and prevailing winds. Emissions-wise, approximately 1.5 million homes use wood for fuel across the UK, and burning wood/coal in open fires and stoves makes up 38 percent.

By comparison, 16 percent comes from industrial combustion, 12 percent from road transport, and 13 percent from the use of solvents and industrial processes. In fact, a wood burning stove emits more particles per hour than a diesel truck.

From outside to in.

Improving outdoor air quality relies on national and societal change, led principally by the government. We’re starting to see more Clean Air Zones being introduced across the UK; these are designed to cut pollution and encourage people to drive less polluting vehicles (i.e. electric and more modern petrol/diesels).

Our indoor air is supplied from outside: both actively through mechanical and natural ventilation, and passively via gaps or leaks in doors, walls, and windows. Only one of these three sources of outdoor air allow us to control the resultant internal air quality.

Ultimately, without improvements and controls to reduce external sources of emissions, the air we need for inside our buildings will only be further polluted.