Surviving the Smog: How to Choose the Best Air Purifier for Delhi Pollution

When AQI levels cross 400 or 500 in Delhi-NCR, a standard air purifier simply isn't enough. You need a machine built for heavy-duty combat against smog, dust, and dangerous PM2.5 particles.

1. CADR is King (Clean Air Delivery Rate)

For Delhi's severe pollution, ignore the marketing fluff and look at one number: CADR. This indicates how much clean air the device produces per hour.

• Small Rooms (Bedroom): Minimum CADR 250 m³/h
• Medium Rooms (Living Room): Minimum CADR 350 m³/h
• Large Halls: Minimum CADR 500+ m³/h

Tip: In Delhi winters, buy a purifier meant for a larger room size than you actually have. This ensures it doesn't have to run at max speed constantly.

2. True HEPA Grade H13 or H14

Ensure the filter is "True HEPA" (Grade H13 or H14). H13 removes 99.97% of particles, while H14 removes 99.995%. Avoid "HEPA-type" or just "High Efficiency" filters which are often inferior and cannot handle the microscopic PM2.5 particles prevalent in smog.

3. Airtight Sealing

A great filter is useless if dirty air bypasses it. Premium brands like Dyson, Coway, and Philips invest in airtight sealing to ensure 100% of the air passing through the machine goes THROUGH the filter, not around it.

4. Heavy Duty Pre-Filter

Delhi air is dusty. A purifier without a good pre-filter will have its expensive HEPA filter clogged with large dust bunnies and hair in weeks. Look for a model with a washable pre-filter to extend the life of your main filters.

Top Recommendations for Delhi 2025