Platon glass tube variable area flowmeters are used to accurately set up air quality monitoring systems, protecting workers from the hazard of airborne dusts and particulates
Environmental sampling systems are used to check the particulates and dust present in the air within factories, or in any work area where activity such as demolition or rebuilding is likely to add dust to the local atmosphere.
Simple low-cost sampling systems can be set up at critical high dust hazard areas, or where personnel that might be affected are working.
These use an air pump to pull the local air through a filter paper, which is then removed on a daily or a weekly basis and sent for laboratory analysis.
To fully assess the results, it is important to set up the air sampling system to extract air at a known flow rate, which establishes the total amount of air passing through the filter.
Platon glass tube variable area flowmeters, manufactured by Roxspur Measurement and Control, are used for this duty: they offer a simple, low cost but accurate flow meter for the air flow rates needed, typically two litres per minute.
With a calibration traceable to National Standards, plus easy to understand glass tube flow indication, the operator or site manager can adjust the flow rate through the filter paper to the right value - and anyone else concerned about health and safety and wishing to inspect the air sample flowrate can also read this value from the meter scale.
Platon G series glass VA flow tubes and meters are used to establish sampling rates in several brands of such environmental sampling equipment.
Higher flowrate versions of the same flowmeters are also installed in sophisticated air extraction duct monitoring systems and continuous effluent monitoring systems (Cems): these are used for effluent monitoring on chimneys and other gaseous discharges to atmosphere, where multiple sensors and detectors are installed, for example on power and chemical plants.