Action layer
Reduce exposure where it is practical, improve the air you control indoors, and route obvious pollution sources to systems that already have enforcement responsibility.
Particles outdoors
A properly worn N95-class particulate respirator can reduce particle exposure. Fit matters: air that leaks around the edges is not being filtered.
Important limitation: standard particulate respirators filter particles; they do not remove harmful gases or vapours.
Surgical mask ≠ N95
Disposable or surgical-style masks can be useful for other purposes, but they are loose-fitting and do not provide the same reliable reduction in small-particle exposure as a tight-fitting respirator.
CDC/NIOSH respirator guidance ↗Exposure beats symbolism
A shorter walk, indoor basketball, a less intense workout or postponing a long outdoor session can reduce the amount of polluted air you breathe. Use the activity planner when an official AQI category is available.
Open activity planner →Indoor air
Source control comes first. When outdoor PM is high, avoid pulling large amounts of that air indoors unnecessarily. Portable particle filtration can supplement source control and sensible ventilation.
1 · Control indoor sources
Cooking, smoking, candles and some cleaning activities can add particles indoors. A purifier cannot fully compensate for a strong source that keeps producing pollution.
2 · Filter particles
For particle removal, choose a portable air cleaner sized for the room. HEPA is a particle-filter standard; CADR tells you how much cleaned air the unit can deliver.
3 · Ventilate intelligently
Ventilation is useful when outdoor air is cleaner. When outdoor pollution is high, opening windows widely can bring more particulate matter indoors; use cleaner-air periods when practical.
Indoor-air helper
Educational calculation only. It does not predict your actual indoor PM2.5 concentration.
Estimated room volume
33.6 m³
CADR ÷ room volume
8.9 room-volumes/hour
How to read this: CADR is a particle-cleaning airflow rating. Dividing CADR by room volume gives a simple equivalent particle-cleaning rate. Higher CADR and longer run time generally mean more air passes through the filter.
Actual indoor PM also depends on outdoor infiltration, open doors/windows, cooking, candles, smoking, room mixing and filter condition. This number is not a medical threshold and is not a guarantee of indoor air quality.
US EPA
Guide to air cleaners in the home ↗
Room sizing, CADR, particle versus gas filtration, filter replacement and the limits of portable air cleaners.
US EPA
What HEPA actually means ↗
HEPA refers to high-efficiency particle filtration. It does not mean every purifier removes gases, odours or every indoor pollutant.
Report pollution
Delhi Air Health is not creating another complaint inbox. The useful thing is to help you document the problem and hand it to an official system that already connects to civic agencies.
Best first route inside Delhi
Delhi's pollution-grievance app routes citizen reports across participating civic agencies. It supports location-based complaints and photo/video evidence.
Delhi-NCR / CPCB route
Sameer provides CPCB AQI information and lets the public lodge and track air-pollution complaints. CPCB's complaint guidance says reports can include photos and location information.
Specific DPCC backup channel
DPCC's current functions page lists a WhatsApp helpline for complaints with pictures or videos of leaf or garbage burning. Use this for that specific issue rather than as a general emergency number.
Before you submit
Use the exact location or let the app capture GPS.
Photograph or record the source only if it is safe to do so.
Choose the closest complaint category rather than a vague description.
Add the time and a short description of what is happening.
Keep the complaint ID so you can track the response.
Do not enter a construction site, private property or confront workers to collect evidence.
Safety boundary
If there is an active fire, immediate danger, a medical emergency or another urgent threat to life or property, use the appropriate emergency service rather than waiting for an environmental complaint workflow.
What this page does not promise
No zero-exposure claim. An N95 or purifier can reduce particle exposure; neither makes polluted air harmless.
No product endorsements. Delhi Air Health explains standards and performance concepts, not brands.
No private complaint database. Reports should go to official systems unless we later have a clear, ethical reason to collect anything ourselves.