Air is all around us, everyday, both indoors and outdoors. It’s an essential element for breathing and staying alive and for this reason measuring air quality is very important as we want to know where air is of highest quality and where improvements can be made.
Measuring air quality can be done either through simple chemical and physical methods or through the use of more sophisticated electronic devices. There are four main approaches in use today: active, automatic, passive, and remote/ long-range. Each method is a little different and depending upon what you want to know about a particular area of air, one may be a better choice in relation to the others.
Active sampling to test air quality involves collecting actual samples of air by pumping the air through a filter or other similar device or chemical solution for a specific period of time and then taking the samples to a lab for testing. Air samples are often taken on several days and several different time periods to see if air quality is consistent or if it is different on particular days or at particular times. Active sampling requires more labor than other methods but on the other hand, it is a great deal less expensive than methods that require electronic devices.
Automatic sampling is conducted through the use of electronic devices that are connected to computers and/ or the internet. Air is tested at one particular point with each device. This type of sampling is generally very detailed and has the ability to tell scientists, researchers, and other observers a great deal about air quality in very specific terms. Different places can be compared to and contrasted against one another in this type of sampling. These samples occur in real time and are known to be very accurate, two aspects that are very advantageous.
Passive sampling occurs through controlling the air at a specific point through the use of physical processes like diffusion. Tubes and steel gauze are use to trap nitrates that can later be tested in a lab. Steel gauze is used at the top of the tube and the bottom of the tube is open to the atmosphere in order to prevent rain and dust from entering the tube. The tubes are sealed before and after exposure to assure that all nitrates were collected at the test site. The distribution and collection involved in this method requires manpower, but is also less expensive than using automatic methods.
Remote or long-range sampling is used to measure concentrations of a range of pollutants in real time. This type of sampling allows observers and researchers to see how air quality changes over time, for example if it gets better or worsens and what conditions may trigger either positive or negative changes.
There are many ways to measure air quality. Your approach depends on what you are specifically looking to measure and over what period of time. The more we know and learn about air quality, the more we can improve it and keep it within safe ranges for humans, wildlife, plants, and other living things. Knowing what air consists of can help prevent health problems and environmentally destructive conditions over time.
