Follow these guidelines to effectively monitor and measure ozone.
Sensor height
Because ozone is heavier than air and tends to sink, concentration gradients are common in rooms and are greatly influenced by air movement and mixing. This means the detection of leaks from ozone-generating equipment should be performed at the most appropriate position for the application.
Gas and vapor dispersion
Ozone is highly reactive and will rapidly react and decompose on organic surfaces such as walls, flooring, furniture, plastic test chambers, people etc. The greater the accuracy of the ozone monitor, the greater the variation in ozone concentration measured.
High accuracy ozone monitors detect differences in ozone concentrations and variations with time. Use monitors with min/max/average measurement cycles to reduce the effect of these fluctuations.
If you’re testing the accuracy of ozone monitors in test chambers, ensure the chamber and devices inside the chamber are clean and non-reactive, e.g. glass or a fluoropolymer.
Monitor placement
The Aeroqual ozone sensor measures the ambient concentration of ozone and must not be placed directly in an ozone stream. Don’t use dusty and dirty air inlets or filters as ozone will react with dust and oils and lower the measured ozone concentration.
- For indoor local area monitoring, attach the monitor to an inert surface with the inlet unobstructed.
- For leak detection, mount the unit near the ozone generating equipment.
Ensure the monitor is protected from water splashing, dust, vibration, excessive heat or cold, high concentrations of ozone and excessive swings in humidity.
False readings
The Aeroqual ozone controller responds selectively to ozone. However, other oxidizing gases such as chlorine and nitrogen dioxide can generate false readings if they’re at high concentrations. High concentrations of hydrocarbon gases such as vapors of alcohol, oils and solvents can reduce and mask the concentration of ozone.
Reliability of smell
Smell is not a reliable test for detecting the presence or concentration of ozone as the odour threshold varies widely between people and is affected by local ambient conditions.