What is air quality?

Air quality is a measure of the cleanliness of the air we breathe. Poor air quality means the air contains air pollutants that can damage our health.

Air pollution generally refers to gases, chemicals and particles that can directly damage human health and the environment.

The main types of air pollution we are concerned with in London in the 21st century are:

• Nitrogen oxides (NOx) - a gas formed when fossil fuels are combusted in engines and in gas heating and cooking appliances

• Particulate matter (PM) - airborne particles formed when fossil fuels are combusted in engines, when solid fuels (wood, coal, charcoal) are burned, from construction and demolition activity and from the abrasion of materials. You may have seen ‘PM10’ and ‘PM2.5’; the number indicates the size of the particles. Smaller particles can enter our lungs and pass into the bloodstream

• Volatile organic compounds (VOC) - a category for airborne chemicals that can be emitted from products including fuels, decorative materials and furnishings, cleaning and personal care products, room sprays and scented air fresheners

• Ozone - a gas formed from the reaction of other air pollutants in the presence of sunlight. High in the atmosphere ozone shields us from solar UV, but at ground level it is an air pollutant that can damage human health, plants and materials

Why does air quality matter for our health?

Exposure to air pollution is linked to a number of serious health conditions affecting the lungs, heart and brain. These include asthma, chronic obstructive pulmonary disease (COPD), lung cancer, heart disease, dementia, and diabetes. Long-term exposure to air pollution is thought to cause as many as 36,000 early deaths every year in the UK, and the illnesses triggered and worsened by air pollution affect the health and wellbeing of many thousands more.

The Healthy Waterways project is seeking to reduce air pollution exposure among the boating community in London and for people living, working and going to school next to London’s inland waterways. Cleaner air is better for everyone’s health.