Is ozone good or bad? A quick guide to ozone measurement

Often it’s a surprise to people to discover that ozone (O₃) gas can be good and bad. O₃ is an important gas in urban pollution monitoring, as well as a gas used in industrial processes. This video hopefully explains it’s two faces in a way that is quick and easy to understand.

The good

In the atmosphere, good O₃ protects us from the sun’s harmful UV rays. Many people know about the hole in the ozone layer that was created by humankind’s use of CFCs. Thankfully CFCs are now banned and the layer hole is shrinking.

The bad

At ground level, in urban environments bad O₃ is created by the reaction of urban pollution and sunlight. Photochemical smog is the technical term for this conversion process. In this way, O₃ becomes a powerful urban pollutant with negative health effects.

The ugly

Breathing even small amounts of ozone can be harmful. Symptoms include: coughing, shortness of breath, and aggravation of lung diseases like asthma. At higher concentrations, you can smell ozone, but it becomes harmful even at lower doses. For that reason, many countries have set an exposure limit of 100 ppb (parts per billion) O₃. In some countries, like Sweden, the limit is set even lower. It is one of six common pollutants limited by the United States Environmental Protection Agencies and other environmental regulators. Exposure to ozone in the workplace is controlled by the Occupational Safety and Health Administration and their counterparts around the world.

Lesser known is that O₃ is a very useful gas for cleaning and sterilizing. Bacteria and odor can be broken down by ozone gas. It is often used in the food industry. For example, for sterilizing fruit and vegetables. It has been used in water treatment plants for many years. Generating O₃ in enclosed spaces can expose people to ozone gas. For example, when machinery leaks. So although ozone is useful it is also important that its use is controlled especially when there are people around.

So measuring and monitoring O₃ is important for human health – outdoors and indoors. The problem is that the equipment for measuring O₃ is either a) accurate but too expensive, or b) affordable but not accurate. This is why Aeroqual came up with option C: monitors that are both accurate and affordable.

Enjoy the video, we hope it’s answered the question – is ozone good or bad?. Be sure to get in touch to talk to us about your application.