What's in my air
Cooking emissions — the highest pollution exposure in most Indian homes
Cooking emissions are the mixture of fine particulates, combustion gases and organic vapours generated by high-temperature cooking, which in most Indian homes produce the day's highest indoor pollutant concentrations.
Limits and standards
India's NAAQS are ambient (outdoor) standards, and there is no statutory Indian indoor air quality standard for homes. WHO's guideline values are health-based targets rather than regulatory limits, and are consistently stricter.
| Standard | Limit | What it means |
|---|---|---|
| India | No indoor standard applies | NAAQS are ambient standards. There is no statutory Indian indoor air quality limit for homes, so the ambient values are the only available reference point. |
| WHO 2021 guideline — PM2.5 24-hour | 15 µg/m³ | A single session of deep frying in an unventilated kitchen can push room PM2.5 into the hundreds of µg/m³ for tens of minutes. |
Where it comes from
Heated cooking oil
Oil above its smoke point produces large quantities of fine aerosol and aldehydes. This happens with any heat source, including induction.
Tadka and dry roasting
Spices in hot oil generate a rapid, intense particulate burst — brief but very high.
Tawa and griddle cooking
Direct contact of food with a hot surface produces sustained particle generation over the whole cooking period.
Gas combustion
Adds NO₂, CO and combustion particulates on top of the food-derived emissions.
Solid fuel
Where wood, dung or coal is used, emissions are dramatically higher and are a recognised public health issue in their own right.
Why it matters
- For a household in a moderately polluted Indian city, cooking is often a larger contributor to daily personal PM2.5 exposure than the outdoor air is.
- The person cooking receives a much higher dose than anyone else in the home, because they are standing directly in the plume.
- The exposure is repeated, daily, and largely unnoticed because the smell is normal and expected.
- It is also unusually tractable. Unlike outdoor air, this is a source inside your own home with a well-understood engineering fix.
Note
Can you detect it yourself?
Consumer air quality monitors are genuinely useful for tracking change and poor at absolute measurement. Knowing which of the two you are looking at prevents most of the disappointment in this category.
| Question | Answer |
|---|---|
| Can you sense it? | Smell and visible haze during frying. The smell fades from awareness quickly, while particle concentrations remain elevated for a long time afterwards. |
| What a consumer monitor shows | This is the most striking demonstration a consumer PM2.5 monitor provides. Place one in the kitchen and watch a single tadka. The readings surprise almost everyone. |
| Field test | Run a monitor through a normal evening's cooking with the exhaust off, then repeat with it on from the start. The comparison is more persuasive than any specification sheet. |
What removes it
Effectiveness ratings below describe the technology working correctly, within its service life, on water or air that suits it. “Depends” means there is a condition in the caveat that decides the outcome — read it before buying.
- Ducted extraction, run from before cooking startsEffective
Capturing emissions at the source before they mix into room air is by far the most effective intervention available.
Caveat: Must vent outdoors. Capture efficiency also depends on the hood covering the burners and being close enough — a decorative chimney mounted high above a wide hob captures poorly.
- Rear-burner cookingPartial
Capture efficiency at rear burners is substantially higher than at front burners under the same hood. Free to adopt.
- Closing the kitchen door while cookingPartial
Contains the plume in one room rather than distributing it through the flat. Combined with extraction, this is most of the achievable benefit.
- Air purifier in the adjacent living spacePartial
Handles what escapes into the rest of the home. A sensible support measure with the kitchen door shut.
- Air purifier in the kitchen itselfMinimal
Fighting a continuously emitting source at close range. It will help slightly and will load the filter fast.
Caveat: Grease aerosol coats and ruins HEPA media quickly. A purifier is not a substitute for a chimney and will cost more to run in that role.
- Lower-temperature cooking methodsPartial
Keeping oil below its smoke point substantially reduces aerosol generation — worth knowing even if it is not always practical.
What does not work
Each of these is commonly assumed — or actively marketed — to help with cooking emissions. None of them do.
Recirculating chimney
Removes grease and some odour, then returns particles and gases to the kitchen. It is a grease filter with a fan, and it is what a large share of Indian flats have installed.
Ionisers
Deposit cooking aerosol on kitchen surfaces, which in a room full of grease is a poor outcome.
Air fresheners
Mask the smell, add VOCs, and change nothing about the particles.
Source control that beats filtration
For most indoor pollutants the highest-leverage intervention is not a device. These are the changes worth making before, or instead of, buying anything.
- Switch the exhaust on before lighting the hob, and leave it running ten minutes after cooking ends. Most of the benefit comes from the timing rather than the equipment.
- Check whether your chimney ducts outdoors. If it recirculates, that is the single most valuable thing to change in the kitchen.
- Close the kitchen door while cooking and keep a kitchen window open where outdoor air permits.
- Cook on rear burners where the dish allows.
- Keep oil below its smoke point — visible smoke from the pan is aerosol you are about to breathe.
Frequently asked questions
Is Indian cooking bad for indoor air quality?
Should I put an air purifier in the kitchen?
Does induction cooking reduce indoor pollution?
How long does cooking pollution stay in the air?
Sources
Every limit and standard quoted on this page comes from one of the documents below. Where a figure is not in one of these, we have not published it.
World Health Organization · published 2021-09-22 · checked 2026-08-01
The 2021 revision tightened most values substantially. WHO guideline values are health-based targets, not regulatory limits, and are considerably stricter than India's NAAQS.
National Ambient Air Quality Standards (NAAQS), notification dated 18 November 2009
Central Pollution Control Board, Ministry of Environment, Forest and Climate Change · published 2009-11-18 · checked 2026-08-01
India's legally applicable ambient air standards. They are ambient (outdoor) standards — India has no equivalent statutory indoor air quality standard for homes.
WHO Guidelines for Indoor Air Quality: Selected Pollutants
World Health Organization · published 2010-01-01 · checked 2026-08-01
Covers formaldehyde, benzene, carbon monoxide, naphthalene, nitrogen dioxide, PAHs, radon, trichloroethylene and tetrachloroethylene specifically as indoor pollutants.
This page states what published standards say and what the physics of each technology allows. It does not state what is in your supply — no page can. Where the two questions meet is a test result, and every entry in this library says which test to ask for.