Guides

Short, sourced answers to the questions people ask in smog season.

• Smog season explained: why Lahore chokes every winterWhy smog builds up over Lahore and Punjab from late October to January, where the pollution comes from, what it does to health, and how to protect yourself and your family.
• What is AQI? The US AQI and PM2.5 explainedWhat the US Air Quality Index means, what PM2.5 is, the six AQI categories, the WHO guideline, and why two apps can show different AQI for the same city.
• Is it safe to run or exercise in smog?When to exercise outdoors in Lahore’s smog and when to move indoors, by AQI level, with the cleanest time of day and what to do if you must train outside.
• Smog and children: school runs, play and masksHow smog affects children, what to do about the school run, outdoor play and PE, masks for children, and where to find official school-closure notices in Punjab.
• How to keep indoor air clean during smogWindows, purifiers, cooking and a do-it-yourself box-fan filter: practical ways to cut PM2.5 indoors during Pakistan’s smog season.
• Modelled vs measured air quality: why the numbers differSaans shows a model forecast for every city and area, and monitoring-station readings where they exist. What each one is, how accurate it is, and which to trust.
• Which mask works against smog? A buying guideWhat protects against PM2.5 smog: N95, KN95, FFP2 and FFP3 explained, how to check a mask is genuine, how to get a good fit, masks for children, and how long to use one.
• Air purifiers for smog: what to buy and what sizeHow to choose an air purifier for Pakistan’s smog: true HEPA vs "HEPA-type", CADR and room size (with a calculator), running costs, and what to avoid such as ozone generators.