Скачать с ютуб How we measure air quality в хорошем качестве

How we measure air quality

Environment Protection Authority Victoria has been monitoring ambient air quality in Victoria since 1979. In that time, our scientific knowledge and procedures have come a long way. Discover what goes on inside EPA’s air monitoring stations and learn about some of the instruments inside the station, what they measure, and how they work. Monitoring air quality is just one of the ways EPA is striving for a healthy environment for all Victorians. Find out more at https://www.epa.vic.gov.au/epaairwatch Video transcript: Eamonn King: G'day I'm Eamonn, I'm an air quality technician with the Environment Protection Authority Victoria or EPA. Ambient air is the air around us that we breathe all the time. Industry and everyday activities like driving a car can impact on the quality of our air. Today I'm going to show you how EPA monitors ambient air quality in Victoria using an air monitoring station such as this one. I'm going to tell you about some of the instruments found in an monitoring station, a bit about what they measure and how they work. On the roof of an air monitoring station you can see a number of inlets. These inlets are connected to instruments inside the station. This glass inlet is connected to a number of instruments which measure gases such as ozone, carbon monoxide, sulphur dioxide and nitrogen dioxide. This inlet draws in air to measure particulate matter 2.5 or PM2.5. The concentration of PM2.5 is one of the more important indicators of healthy air. PM2.5 particles are extremely small particles present in smoke and in some fine dusts. They measure 2.5 micrometers or less in diameter. To give you an idea of how small it is a strand of hair is about 75 micrometers in diameter. So these particles are over 30 times smaller than that. I'm going to take you into the station now. It can be a bit noisy because equipment has to run 24 hours a day. This is connected to the glass inlet we saw on the roof. An air sample travels down and is distributed to the various analysers. Each one of these measures a particular gas. Sulphur dioxide, carbon monoxide, nitrogen dioxide and ozone. The instrument here is a Beta Attenuation Monitor. It measures those tiny particles I mentioned earlier. Inside this instrument is a roll of tape. The particles which come down the inlet are deposited on the tape. As you can see when these tidy particles land on here the tape can sometimes change colour. All the air quality data collected by the different types of instruments inside the air monitoring station is sent to this computer, 24 hours a day 365 days of the year. From here the data is sent to our computer and then goes up on the EPA's website. EPA's scientists also use this data to prepare daily air quality forecasts and summaries. EPA has been monitoring ambient air quality in Victoria since 1979. Technology has come a long way since then and so have we. EPA is always exploring the use of new technologies and better ways to monitor our air and provide up-to-date air quality data to the Victorian community. This is just one of the ways EPA is striving for a healthy environment for all Victorians.