When the PSI starts climbing during haze season, most of us think about what's happening outside — visibility, masks, cancelled outdoor plans. But a lot of haze-related irritation actually happens indoors, once fine particles work their way into homes and offices. Here's a practical, room-by-room look at keeping your indoor air clean when the haze rolls in.
1. Check the PSI before you open a single window
The NEA's myENV app and the National Environment Agency website update PSI readings regularly, and it's worth checking before you air out your home. On "moderate" days, ventilation is still fine. Once readings tip into "unhealthy" territory, it's better to keep windows and doors closed and rely on air circulation indoors instead.
2. Seal the gaps, not just the windows
Haze particles are small enough to sneak through door gaps, aircon vents, and exhaust fan openings. A simple draft stopper under doors, and keeping bathroom exhaust fans off when not in use, can meaningfully reduce how much haze finds its way inside during bad air days.
3. Air purifiers work, but placement matters
A purifier tucked in a corner behind furniture won't do much. Central, open placement — away from walls, ideally in the room you spend the most time in — lets it actually cycle through the air effectively. If you only own one unit, the bedroom is usually the best choice, since that's where you spend the most consecutive hours breathing the same air.
4. Masking up indoors isn't overkill on bad days
On very high PSI days, even indoor air in older or less sealed homes can carry noticeable particulate levels. If you're doing housework, cooking, or any activity that stirs up dust during a haze episode, a well-fitted N95 mask indoors is a reasonable precaution, not an overreaction.
5. Give your respiratory system some extra support
Haze season is exactly the kind of period where many people in Singapore lean on traditional herbal ingredients like Cordyceps and Lignosus (tiger milk mushroom) as part of their routine, alongside the practical steps above. Our earlier piece on Singapore's climate and your lungs goes into more detail on year-round respiratory care, including GreenKare's Lignotiger Lung Cleanse capsules. As always, speak with a doctor or licensed TCM practitioner first if you have an existing respiratory condition.
The bottom line
Haze season doesn't stay outside — fine particles find their way indoors more easily than most people expect. Checking the PSI, sealing common entry points, placing your air purifier well, and masking up for dusty indoor tasks are simple, practical habits that go a long way toward protecting your lungs when the air quality dips.
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This article is for general informational purposes only and is not medical advice. If you have ongoing respiratory symptoms or a chronic condition, please consult a doctor or qualified healthcare professional.