Air pollution results from the introduction of a range of substances into the atmosphere from a wide variety of sources. It can cause both short term and long term effects on health, but also on the wider environment. The air quality in Scotland is generally better now than it has been at any time since before the Industrial Revolution.
These improvements have been achieved through the introduction of legislation enforcing tighter controls on emissions of pollutants from key sources, notably industry, domestic combustion and transport. However, despite the improvements made, air pollution is still recognised as a risk to health, and many people are concerned about pollution in the air that they breathe.
The AQI is an index for reporting daily air quality. It tells you how clean or polluted your air is, and what associated health effects might be a concern for you. Think of the AQI as a yardstick that runs from 0 to 500. The higher the AQI value, the greater the level of air pollution and the greater the health concern. For example, an AQI value of 50 represents good air quality with little potential to affect public health, while an AQI value over 300 represents hazardous air quality.
AQI values below 100 are generally thought of as satisfactory.
Particle pollution, also called particulate matter or PM, is a mixture of solids and liquid droplets floating in the air. Some particles are released directly from a specific source, while others form in complicated chemical reactions in the atmosphere.
Particles come in a wide range of sizes.
Coarse dust particles (PM10) are 2.5 to 10 micrometers in diameter. Sources include crushing or grinding, some agricultural operations and dust stirred up by vehicles on roads.
Fine particles (PM2.5) are 2.5 micrometers in diameter or smaller, and can only be seen with an electron microscope. Fine particles are produced from all types of combustion, including motor vehicles, residential wood burning, fires and some industrial processes.
Locally, we have been measuring the levels of air poluution in Abernyte via two sensors at Infield. You can see the sensor results in real time by visiting the Abernyte air quality page. The map shows the location of the Abernyte sensors and the few other similar sensors in our area. The colour of the marker is an indication of the current air quality as per the AQ Index above.
Clicking on the marker and then on the + that appears beside the sensor name allows you to see the graph of the past 24 hours and 5 days readings.
Abernyte's air quality is very good and seldom varies from within the green zone of cleanest air. Yet within those readings they can and do vary from near zero pollutants and on occasion in to the yellow moderate band, mostly from the output from woodburning stoves and open fires. The readings from these sensors can only give an indication of the air quality. For the official Scottish air quality results from the official and calibrated sensors you need to go to the Scottish Government's air quality page here. This monitoring is mostly in urban areas of high traffic density but is using the same index as our local sensors.