What does PM2.5 mean and is it dangerous?

PM2.5 particles are airbourne and small enough to enter the body through regular breathing. In fact, they are so small that they can penetrate the lungs, enter the bloodstream, and affect the heart.

Exposure to high levels of PM2.5 for just one day have been linked to eyes, nose and throat irritation, asthma attacks, respiratory symptoms, chronic bronchitis, and heart attacks in people with heart disease. While prolonged exposure for months and years can increase the risk of asthma, heart disease, premature death, and even affect fetal growth in pregnant people.

It is impossible to prevent exposure to PM2.5 particles but you can limit it. Since fire and smoke are such large contributors, the best advice is to monitor how much time you spend around them.

Some easy steps are to cut out the use of wood-fired stoves and heaters, limit candles and incense in the home, don’t smoke cigarettes (or at least don’t smoke them inside), and use the exhaust fan above your gas cooktop. On smokey days, you should also keep your windows and doors closed and try to stay inside as much as possible, and wear a mask if you do have to leave the house. Just make sure it is a certified PM2.5 mask with a removable filter or an N95 (you may still have some of these laying around).

Gas heaters can also emit PM2.5 particles, but these are much lower than anything that puts out smoke. Regardless it is better to avoid unflued indoor gas heaters (for both PM2.5 and carbon monoxide reasons), or if they're being used make sure you're following the safety protocols.

When it is clear out, throw open the doors and windows to remove indoor pollutants and any moisture build up. In particularly moist areas like laundries and bathrooms, use the exhaust fan to circulate the air to help fight against mould and move any particles out of the space.

It may also be worth investing in a good quality air purifier that has a HEPA 13 filter, capable of filtering out PM2.5 particles. Most high end air purifiers are equipped with this kind of filter, and even some budget devices like those from Kmart. But some cheap options like the Ikea range are only EPA certified so they won’t do much to protect your lungs.

Luckily there are plenty of resources out there that help you keep track of the PM2.5 levels.

All state governments use a similar system for tracking the air quality index. Across the country different state governments rate the air quality from Good, through to Extremely Poor on a hourly basis. In many cases these are split into districts, and show everything from PM2.5 ratings, through to carbon monoxide, ammonia, and sulfar oxide.

Here are the best links per state;

• NSW
• Queensland
• Victoria
• South Australia
• Northern Territory
• Tasmania
• Western Australia

Indoors you'll need to get your own air quality sensor to be able to keep tabs on your PM2.5 levels. Most air purifiers have a built in sensor, but you can also buy them as standalone devices if you'd prefer. These tend to give you other information like humidity levels, temperature, and even if formaldehyde is in the air.

Here are some options;