GRAP Stage 1 to 4: What Changes at Each Level?

Air pollution in Delhi-NCR can change significantly depending on weather conditions, emissions and atmospheric dispersion. To respond to worsening air quality, authorities use the Graded Response Action Plan (GRAP), a framework that introduces progressively stronger measures as pollution levels deteriorate.

For businesses, industries, construction companies, transport operators and facilities using diesel generator sets, understanding the four GRAP stages can help with advance planning.

The framework is particularly important because the restrictions are not identical at every level. As the situation moves from Stage-I toward Stage-IV, the number and intensity of pollution-control measures increase.

For a detailed explanation of the different GRAP levels and their practical implications, readers can also refer to Aceget's article, GRAP Stage 1 to 4: What Changes at Each Level?.

What Is GRAP?

The Graded Response Action Plan is a set of emergency pollution-control measures applicable across Delhi-NCR. The measures are activated depending on the prevailing and forecast air-quality conditions.

The Commission for Air Quality Management (CAQM) is responsible for implementing the GRAP framework in the National Capital Region.

The latest revised schedule was approved by CAQM on 29 September 2026. According to the Ministry of Environment, Forest and Climate Change, the revised framework contains 25 actions under Stage-I, 8 under Stage-II, 10 under Stage-III and 5 under Stage-IV.

Businesses should therefore refer to the latest CAQM schedule rather than relying exclusively on older GRAP articles or previous-year restrictions.

Stage-I: Poor Air Quality

Stage-I represents the first level of the GRAP response and applies when air quality enters the Poor category.

The objective at this stage is to control pollution before conditions become substantially worse.

Measures can involve areas such as:

• Road-dust management

• Construction and demolition activities

• Waste management

• Traffic and transportation

• Industrial pollution

• Public awareness

• Pollution monitoring

The latest September 2026 revision consolidated several repeated measures and increased the number of actions covered under Stage-I. Importantly for businesses using DG sets, certain DG-set-related actions were moved from Stage-II to Stage-I.

This means businesses should not wait for air quality to reach the "Very Poor" category before reviewing their DG-set and emission-control arrangements.

Stage-II: Very Poor Air Quality

Stage-II applies when air quality deteriorates into the Very Poor category.

At this point, additional restrictions and pollution-control measures are introduced.

Businesses may experience greater scrutiny of pollution-generating activities, while authorities can intensify dust control, traffic management, industrial-emission control and other measures.

The revised September 2026 schedule contains 8 actions under Stage-II.

For facility managers, Stage-II is a useful reminder that pollution-control planning should already be in place rather than being developed after restrictions become stricter.

Stage-III: Severe Air Quality

Stage-III represents a significantly more serious pollution situation.

At this level, authorities introduce stronger measures intended to reduce emissions from major pollution sources.

Depending on the applicable CAQM directions, businesses and project operators may need to pay particular attention to:

• Construction and demolition activities

• Dust-generating operations

• Industrial emissions

• Vehicle movement

• Generator-set operation

• Transportation restrictions

• Fuel and operational requirements

The revised 2026 framework contains 10 actions under Stage-III.

Because measures can affect day-to-day business operations, companies operating in Delhi-NCR should maintain contingency plans before Stage-III conditions arise.

Stage-IV: Severe Plus Air Quality

Stage-IV is the most severe level of the GRAP framework.

It is associated with extremely poor air-quality conditions and introduces the strongest restrictions.

Stage-IV can have a major effect on transportation, construction, industrial activity and other pollution-generating operations.

The latest revised schedule contains 5 actions under Stage-IV.

The history of 2026 also shows that GRAP stages can be invoked and subsequently revoked as air quality changes. For example, CAQM invoked Stage-IV in January 2026 and later revoked it when air quality improved.

This dynamic nature is one reason businesses should monitor official CAQM announcements regularly.

What Does GRAP Mean for DG Sets?

Diesel generator sets are particularly relevant because their exhaust emissions contribute to air pollution.

CAQM has issued separate directions concerning the use and regulation of DG sets in NCR. These directions have included provisions related to emergency use, regulated operation, dual-fuel systems and emission-control arrangements for applicable categories.

The regulatory framework has evolved over time, so businesses should check the latest applicable CAQM directions rather than assuming that an old DG-set restriction still represents the current requirement.

The CAQM official website is the most important source for current GRAP schedules, implementation orders and related directions.

Why Businesses Should Prepare Before Restrictions Increase

GRAP is designed as a graded response. That means businesses have a strong reason to prepare before the most severe stages are activated.

A facility manager can review:

DG-set details:
Capacity, fuel type, engine condition and operating pattern should be documented.

Emission-control arrangements:
Where applicable, businesses should evaluate suitable emission-control systems and maintain supporting records.

Alternative power sources:
UPS systems, batteries and other power-continuity measures can help reduce dependence on diesel generation.

Construction activities:
Companies carrying out construction or demolition should prepare dust-control measures in advance.

Documentation:
Maintenance records, test reports and equipment information should be organised and readily available.

Regulatory monitoring:
Someone within the organisation should be responsible for monitoring CAQM notifications and changes to applicable requirements.

Why the Latest GRAP Schedule Matters

One common mistake is treating GRAP as a fixed set of restrictions that remains unchanged every year.

In reality, CAQM can revise the schedule and modify individual measures based on pollution-control requirements.

The September 2026 revision is a good example. It changed the distribution of measures between stages and specifically moved DG-set-related actions from Stage-II to Stage-I.

Therefore, businesses should always check the latest official schedule before making compliance or operational decisions.

Useful Official Resources

For accurate and updated information, businesses should rely primarily on government and regulatory sources.

The Commission for Air Quality Management (CAQM) publishes GRAP schedules, implementation orders, revocation orders and other directions for Delhi-NCR.

The Ministry of Environment, Forest and Climate Change (MoEFCC) provides official information about national environmental policies and regulatory developments.

The Central Pollution Control Board (CPCB) provides air-quality monitoring information, AQI resources and broader pollution-control information.

Conclusion

GRAP provides a staged approach to managing air pollution in Delhi-NCR. As conditions deteriorate from Poor to Very Poor, Severe and finally Severe Plus, progressively stronger measures can be introduced.

For businesses, the key lesson is simple: do not wait for Stage-III or Stage-IV to start preparing.

Facilities using DG sets should understand their applicable requirements, maintain equipment properly, evaluate appropriate emission-control solutions where required and keep track of CAQM updates.

Because the GRAP framework can be revised and individual stages can be invoked or revoked according to air-quality conditions, using current official information is essential.