Air
What is GRAP, and when does each stage bite?
The Graded Response Action Plan is the rule that decides what Delhi-NCR shuts down when the air gets bad, and at what number. It has four stages. Each one is keyed to Delhi's own AQI, so the trigger is arithmetic rather than judgement — but who invokes it, and when, is a decision taken by a sub-committee of the Commission for Air Quality Management, not something that happens automatically at the threshold.
Four stages, keyed to the index Delhi already publishes
The thresholds are not new numbers. They are the CPCB band boundaries, with one exception.
GRAP stages sit on top of the CPCB National Air Quality Index. Stage I begins where the 'Poor' band begins, Stage II where 'Very Poor' begins, Stage III where 'Severe' begins. A reader who already knows the bands already knows three of the four triggers.
The exception is Stage IV. 'Severe' runs to the top of the CPCB scale, but GRAP splits it: Stage IV is invoked above 450, which is not a band boundary anywhere in CPCB's table. It is the one GRAP threshold that has to be learned separately.
The Commission revised the schedule on 21 November 2025, and the direction of the change is the thing worth knowing. Measures did not get harsher — they got earlier. Staggered office timings moved from Stage III to Stage II. Work-from-home decisions moved from Stage IV to Stage III. Uninterrupted power supply, traffic synchronisation, public-transport augmentation and public alerts all moved from Stage II down to Stage I. The same restrictions now arrive at a lower number than they did the winter before.
- GRAP
- Graded Response Action Plan. An emergency response schedule for the whole of NCR, keyed to Delhi's average AQI and to weather forecasts.
- CAQM
- The Commission for Air Quality Management in NCR and Adjoining Areas. It writes the schedule, and its Sub-Committee on GRAP is what actually invokes and revokes a stage.
- Invoked
- A stage is in force because the Sub-Committee ordered it, not because a number was crossed. The threshold is when they may act, not when it happens.
- Extant GRAP
- The Commission's own term for whichever version of the schedule is currently in force. It is not a fixed document.
Where each stage begins
Delhi AQI, as the Commission states it. Three of the four are CPCB band boundaries; the fourth is not.
Stage I — ‘Poor’
201 – 300 AQI
CAQM, revised schedule 21 November 2025
Stage II — ‘Very Poor’
301 – 400 AQI
CAQM, revised schedule 21 November 2025
Stage III — ‘Severe’
401 – 450 AQI
CAQM, revised schedule 21 November 2025
Stage IV — ‘Severe+’, above
450 AQI
CAQM, as stated when Stage IV was invoked
How to read a GRAP claim
Four checks, and the headlines fail the first two more often than not.
Which schedule? The stages were amended on 21 November 2025 and the measures under each moved. A piece written the winter before describes restrictions that now sit a stage lower, and it will look authoritative while being wrong.
Invoked, or merely crossed? An AQI of 410 does not put Stage III in force. The Sub-Committee has to order it. Reports that say a stage 'kicked in' when the number moved are describing the threshold, not the order.
Whose AQI? The triggers are stated against Delhi's daily average, not a station reading and not your neighbourhood. The worst monitor in the city can sit two bands above the figure the stage is keyed to.
Forecast or observation? The Commission acts on forecasts as well as readings, and has invoked a stage pre-emptively before the average reached it. A stage in force is not proof the threshold was crossed.
What it does not measure
- It cannot tell you whether a stage is in force today. That is an order issued by the CAQM Sub-Committee, published case by case, with no feed behind it — this page states the schedule, not the status.
- It cannot give you the full list of restrictions under each stage. The complete extant schedule is a CAQM document that is amended without a version number, and reproducing it here would create a second copy that goes stale silently. The Commission's own site is linked below.
- It cannot tell you what is enforced. A measure being in the schedule and a measure being applied on a given street are different claims, and nothing in the published record connects them.
- It cannot be read backwards into health. The stages are an administrative trigger keyed to an index, and the index is not a dose.
Where this comes from
Every figure above comes from one of these.
- CAQM revises GRAP schedule, making it more stringent Press Information Bureau, Ministry of Environment, Forest and Climate Change · The 21 November 2025 revision, and the source for Stage I, II and III ranges and for every measure named above as having moved.
- CAQM invokes Stage-IV of extant GRAP in entire Delhi-NCR Press Information Bureau, Ministry of Environment, Forest and Climate Change · States Stage IV, ‘Severe+’, as Delhi AQI above 450. The revision release does not give Stage IV's trigger.
- GRAP orders and the extant schedule Commission for Air Quality Management in NCR and Adjoining Areas · The Commission's own orders, including whichever schedule is currently in force.
Reuse freely — CC BY 4.0. Each source above keeps its own terms.