
We've heard the dreaded haze is coming back. Should we just stay indoors? Do face masks help? We explain PSI, precautions to take and the pros of air purifiers.
Those seasoned Singaporeans or long-term residents among you will nod in agreement when we say 2015 was one of the most prolonged and destructive examples of the haze in Singapore yet. We’ve heard from CNA that there’s a severe risk of haze returning to Singapore this July, so what can we do to prepare?
If you’ve been getting headaches in the afternoon, a dry throat, coughing or itchy skin, you’re most likely feeling the effects of the poor air quality – and children and asthmatics are more likely to suffer from the smoke in the air. But do we need to admit defeat and keep all our activities indoors until it passes? Is it really safer for your children to wear a mask? And do we even want to go back to masks post-covid? Here’s how to understand PSI and the precautions to take so that your family can breathe easy…
What really causes haze?
Can you smell smoke in the air? Periodic forest fires in Sumatra, Indonesia (sometimes lit illegally) are mostly the culprit. A cheap method of clearing land, fire is used for deforestation, often to make way for plantations for the palm oil industry. Just one of the devastating environmental effects is the hazardous smog that spreads across Singapore, Malaysia and beyond.
We can be part of the solution: look for Certified Sustainable Palm Oil (CSPO) and FSC certified or 100% recycled pulp and paper options when shopping for your family, and think about taking the pledge to demand sustainably produced palm oil.
More acronyms to learn: AQI and PSI

Air Quality Index (AQI) is a measure of the level of pollutants in the air. See www.aqicn.org to check real-time readings in Singapore. In Singapore, our variant of Air Quality Index is known as Pollutant Standards Index (PSI). The National Environment Agency (NEA) calculates the PSI by taking an average reading over 24 hours of six pollutants: particulate matter (PM10), fine particulate matter (PM2.5), sulphur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), and carbon monoxide (CO). The pollutant that wreaks the most havoc during haze episodes is fine particulate matter: PM2.5. This refers to fine particles of 2.5 microns or smaller – up to 30 times smaller than the thickness of a strand of hair.
How haze affects us

The haze can cause particles in the air to get trapped in our lungs that are difficult to eliminate. People most at risk are those with impaired lungs, heart problems and allergies such as asthma. The NEA suggests pregnant women also reduce their exposure during haze episodes.
Healthy people who spend a lot of time outdoors can be affected, too. Air quality is considered ‘unhealthy’ once the PSI rises above 101. The NEA advises that when the PSI levels are at the high end of ‘moderate’ to ‘unhealthy’, we can limit the effects by reducing outdoor activities and physical exertion, especially people who are more sensitive to air pollution.
What precautions to take
- If you’re concerned, you can wear an N95 mask outdoors, especially if undertaking strenuous and prolonged activity. An N95 mask covers the nose and mouth and helps protect you from breathing in some hazardous substances, as well as small particles in the air. These masks are said to block out 95 per cent of small particles in the air you breathe and are available at clinics, pharmacies and major supermarkets. The fashion-conscious among you might want to check out Airinum, a stylish brand of masks that boasts three-layer filter technology. Head to Ante, Singapore’s largest stockist of these masks, to stock up.
- Young children, pregnant women and the elderly should avoid using these masks due to the respiratory effort involved in using them. We consulted medical experts for our article on the suitability of haze masks for infants and children, which is an essential read for parents.
- The safest way to escape the haze is to remain indoors as much as possible and reduce exposure. Keep windows and doors closed.
- Make sure everyone in the family is drinking plenty of water – if you’re coughing, your airways may be inflamed from all the dust particles in the air.
- If you wear contact lenses, reach for your glasses instead. Contacts can aggravate any burning or itching sensations in the eye caused by air particles.
- Use lots of moisturiser to help prevent itching!
- Download the myENV app for Apple and Android to get regular updates on the PSI so you can plan your family’s activities and know whether to avoid the outdoor playground or your morning jog.
Investing in an air purifier

Air purifiers reportedly help remove pollutants and allergens swirling around, making air cleaner to breathe, but you need to make sure you buy the right one for the job as not all of them are equipped to deal with conditions created by the haze. Air purifiers built with HEPA, or High Efficiency Particulate Air, filters are capable of removing 99.7 per cent of particles that are 0.3 microns or larger, making them better at managing the haze than UV, carbon or photocatalytic filters.
Other considerations:
- Selecting a model with an inbuilt fan will mean the machine can suck in air and clean it more efficiently. The downside is that it can be noisier. Check out the decibels in-store before you buy.
- While a small air purifier will do the job for smaller rooms such as a bedroom, a larger space demands a bigger unit, so be sure to check how much ground the model can reasonably cover.
- Placement matters when deciding where to put the unit. Locate the air purifier where the most air can pass through it freely.
- With some tender loving care, your air purifier will care for your family more effectively. Change filters and clean the electrostatic collection plates regularly.
Lead image: August de Richelieu via Pexels