What AQI level is unsafe for my child to play outside in Kathmandu?

As a simple rule, outdoor play is generally fine when the AQI is below 100. Between 101 and 150 (the 'unhealthy for sensitive groups' band), children — especially those with asthma — should cut back on long or vigorous outdoor activity. At 151 and above, keep outdoor time short and use a well-fitted mask, and at 201 or higher keep children indoors as much as possible. Children with asthma may react at lower numbers, so watch your own child's symptoms alongside the AQI.

Do cloth or surgical masks protect my child from PM2.5?

Not very well. Fine PM2.5 particles slip through and around loose cloth or surgical masks. On higher-pollution days, a certified respirator sized for children — labelled N95, KN95 or FFP2 — with a good seal over the nose and cheeks filters far more. Fit matters as much as the rating: if the mask gapes at the sides, it offers little protection. Masks are not suitable for infants and very young toddlers; for them, focus on clean indoor air instead.

Is an air purifier worth it for a child's room in Nepal?

For many Valley families it can help. A purifier with a true HEPA filter, rated for the room's size, measurably lowers indoor PM2.5 — most useful in the bedroom overnight with the windows closed. It is one helpful layer, not a complete fix: pairing it with closed windows during smoky peaks, no indoor incense or smoke, and damp-dusting does more than any single device. If cost is a concern, a clean, well-sealed sleeping room and avoiding indoor smoke sources still make a real difference.

My child coughs every winter — is it the pollution or just colds?

Both are common in the Valley winter, and they can overlap. Seasonal viral colds are frequent, but air pollution can trigger coughing, wheezing and chest infections and make existing asthma harder to control. Because the two look similar, a cough lasting more than a couple of weeks, wheezing, fast or laboured breathing, or repeated chest infections is worth discussing with your doctor, who can check for asthma or infection and guide treatment.

Protecting Little Lungs in Kathmandu's Polluted Air: A Parent's Seasonal Plan

A calm, evidence-based seasonal plan for reading the daily AQI, fitting a mask that seals, and keeping your child's air clean through the Valley winter.

If you live in the Kathmandu Valley, you already know the feeling: a winter morning when the hills disappear behind a grey haze, and your child wakes with a cough that lingers. Air pollution can feel overwhelming because it is invisible and everywhere. But protecting your child's lungs is largely about a handful of simple, repeatable habits — reading the daily air quality number, fitting a mask that actually seals, keeping one room's air clean, and knowing when to call your doctor. This is a calm, seasonal plan you can follow each winter.

Why children's lungs need extra care

Children are not small adults when it comes to breathing. According to UNICEF and WHO, a child's lungs, brain and immune system are still developing, their airways are more permeable, and they breathe faster — taking in more air relative to their body weight than an adult. That means a child absorbs proportionally more of whatever is in the air. The pollutant that matters most is PM2.5: fine particles smaller than 2.5 microns, small enough to travel deep into the lungs and even into the bloodstream.

WHO and UNICEF describe air pollution as a leading environmental health risk to children worldwide, linked to pneumonia, bronchitis and asthma, and able to make existing conditions harder to manage. In Nepal, respiratory infection has long been one of the most common reasons young children are brought to a health post — and the Valley's winter haze coincides with the season when hospitals see the most childhood pneumonia and wheezing. None of this means your child is destined to fall ill; it means the air is a factor worth managing, the same way you manage warm clothing or clean drinking water.

39 µg/m³Kathmandu's average PM2.5 in 2025 (IQAir) — about 7–8 times the WHO annual guideline of 5 µg/m³, with winter and pre-monsoon months the highest.

Step 1 — Learn to read the daily AQI

The single most useful habit is checking the Air Quality Index (AQI) each morning, the way you check the weather. Free apps and sites such as IQAir, AQI.in and the government's monitoring stations report a Valley number updated through the day. The AQI is colour-coded, and you only need to remember roughly what the bands mean for a child.

0–50 (Green, Good): Normal outdoor play is fine. A good morning for the park or walking to school.
51–100 (Yellow, Moderate): Generally okay for most children. If your child has asthma, watch for symptoms and keep their reliever inhaler handy.
101–150 (Orange, Unhealthy for Sensitive Groups): Children, and especially those with asthma, should reduce long or intense outdoor activity. Shift play to later in the day if the number drops.
151–200 (Red, Unhealthy): Keep outdoor time short, choose a well-fitted mask outside, and run a clean-air room at home.
201+ (Purple/Maroon, Very Unhealthy or worse): Keep children indoors as much as possible, close windows, and use an air purifier if you have one.

Step 2 — Fit a mask that actually seals

A mask only protects if it fits. A loose surgical or cloth mask lets fine particles flow in around the edges. For higher-pollution days, look for a certified respirator sized for children — labelled N95, KN95, or FFP2 — and check these points before heading out.

Choose a child or small size; an adult mask will gape at a small face.
Press the metal strip over the bridge of the nose so there are no gaps at the cheeks.
Do a quick seal check: ask your child to breathe out gently — the air should warm the mask, not leak past the eyes or sides.
Swap to a fresh mask when it is damp, dirty or visibly worn; moisture reduces both fit and filtering.
Skip masks for infants and very young toddlers — they do not seal well and can interfere with breathing. For babies, focus on clean indoor air and limiting outdoor exposure on high-AQI days.

Step 3 — Make one room a clean-air refuge

You cannot filter the whole Valley, but you can keep the air clean in the room where your child sleeps and plays. The goal is one reliably cleaner space, not a perfect house.

Close windows on high-AQI days, particularly during the smoky early-morning and evening peaks. Open up to air the room when the AQI dips.
Run an air purifier with a HEPA filter in the bedroom if you can. Choose one rated for the room's size and replace filters on schedule. Even a few clean-air hours overnight helps.
Cut indoor sources: avoid burning incense, mosquito coils or rubbish indoors, and keep cooking smoke ventilated. WHO and UNICEF note that household smoke is a major contributor to children's exposure, alongside outdoor air.
Damp-dust and mop rather than dry-sweeping, which lifts settled particles back into the air.
Keep the home strictly smoke-free — second-hand tobacco smoke adds directly to a child's particle load.

Step 4 — Strengthen the body underneath

Clean air works best alongside a healthy child. Keeping routine immunisations up to date through Nepal's national schedule — including the pneumococcal (PCV) and measles-rubella vaccines — lowers the risk of the serious chest infections that pollution can worsen. Breastfeeding for infants, a varied diet with seasonal vegetables and fruit, warm clothing in winter, and good hand-washing all help a child's lungs and immune system cope. For a child with diagnosed asthma, the most protective single step is using their prescribed preventer medicine exactly as your doctor advises, so the airways are calmer before pollution rises.

Your simple seasonal rhythm

You do not need to do everything at once. Through the high-pollution months — roughly November to May in the Valley, with relief arriving in the monsoon — let a small routine carry you: check the AQI each morning, pick the cleaner window for outdoor play, fit a sealing mask on red days, run a clean-air room at night, and keep vaccines and asthma medicines current. These steps are modest on their own, but together they meaningfully lower how much polluted air your child breathes across a winter — and that is exactly the kind of quiet, preventive habit that protects little lungs over a lifetime.

Around 93 per cent of children under 15 worldwide breathe air polluted enough to put their health and development at risk.
WHO / UNICEF