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What do we breathe? Understanding air quality

Updated: Oct 3, 2022

The issue of air quality is becoming increasingly topical. Not only is there a growing collective awareness of its importance, but more and more people are taking notice of the air quality level in their area and the factors that affect it.

But what do we really mean by air quality and how do we measure it? This article breaks down the details, explaining what air quality is, what air quality indexes are and why they’re important.

cloud represent clean air. What do we breathe

What is air quality and how is it measured?

Air quality is a term used to describe how polluted the air is, usually in a particular area.

Air quality can fluctuate depending on the amount of pollutants in the air, the rate at which they’re released into the air and how long they stay in the atmosphere. Poor air quality can affect the health of those who breathe it in, which is why it’s such a cause for concern.

According to our Research and Development department, there are two substances that affect air pollution:

  • Pollutants: breathing these in causes immediate damage, so they cause direct harm to human health. Among the most common are: particulate matter, carbon monoxide, nitrogen oxide, ground-level ozone and sulphur dioxide.

  • Contaminants: these substances contribute to the warming of the atmosphere and climate change and therefore have an "indirect" effect on human health, but that is equally harmful. Some examples of contaminants include CO2 and methane (CH4).

What is the Air Quality Index?

Air quality index (AQI) is a type of report that indicates the level of pollution in the air. It’s used as a guide to communicate air quality, whether good or bad, in an immediate and simple way, usually through a colour-coded table. When air pollution reaches dangerous levels, local councils and weather forecasters can warn the public using the AQI as a reference.

Each country is responsible for monitoring its air quality and producing its own index. Different countries use different point scales, or standards, to measure air quality and some areas don’t measure the same pollutants as others. All indices are based on the values ​​of pollutant concentrations, whether measured, estimated or forecast.

Indices are important because they allow citizens to assess the levels of air quality themselves and decide on the best practices based on the level of risk, which is especially crucial for people in vulnerable categories.

WHO air quality guideline levels are lower than 15 years ago