Background
What is GRAP?
The Graded Response Action Plan (GRAP) is a framework of emergency measures designed to control air pollution through progressively stricter restrictions as air quality deteriorates.
Introduced: January 2017, following directions from the Supreme Court.
Initial implementing authority: Environmental Pollution (Prevention and Control) Authority (EPCA).
Present implementing authority: Commission for Air Quality Management (CAQM), which replaced the EPCA in 2021.
Coverage: Delhi and the relevant National Capital Region districts of Haryana, Uttar Pradesh and Rajasthan.
Objective: Reduce emissions from major pollution sources during periods of deteriorating air quality.
Nature: Primarily a short-term, emergency pollution-control mechanism.
Why does air pollution increase during winter?
Winter pollution results from a combination of increased emissions and unfavourable atmospheric conditions.
Meteorological factors
Low wind speeds reduce the dispersion of pollutants.
Temperature inversions can trap pollutants close to the ground.
A shallow atmospheric boundary layer limits vertical mixing.
Low temperatures and high humidity can contribute to the formation of secondary particulate matter and haze.
Human-induced factors
Vehicular emissions from petrol and diesel vehicles.
Construction and road dust.
Industrial emissions and diesel generator sets.
Crop-residue burning in neighbouring agricultural States.
Firecrackers during the festive season.
Burning of waste, biomass and solid fuels.
Understanding the Air Quality Index
The AQI communicates the level of air pollution and its potential health effects in a simplified form. India's AQI considers eight pollutants, including PM2.5, PM10, nitrogen dioxide, sulphur dioxide, carbon monoxide, ozone, ammonia and lead.
Fine particulate matter, particularly PM2.5, is a major concern because it can penetrate deep into the lungs and enter the bloodstream, increasing the risk of respiratory and cardiovascular diseases.
Key features
Stage I: Poor air quality
Major measures include:
Strict enforcement of pollution-under-control (PUC) certificates.
Action against visibly polluting vehicles.
Dust-control measures at construction and demolition sites.
Mechanised sweeping and water sprinkling on roads, where appropriate.
Prevention of open waste burning and proper management of municipal solid waste.
Restrictions on the use of diesel generator sets as a regular source of power, subject to applicable provisions and exemptions.
Public awareness campaigns encouraging cleaner transport and reduced pollution.
Stage II: Very poor air quality
More frequent mechanised road sweeping and water sprinkling.
Enhanced public transport services and parking-related measures to discourage private vehicle use.
Restrictions on the use of diesel generator sets, subject to applicable exemptions.
Intensified monitoring of industrial emissions, construction dust and other pollution sources.
Stage III: Severe air quality
A ban on construction and demolition activities, subject to specified exemptions.
Restrictions on BS-III petrol and BS-IV-and-below diesel light motor vehicles in Delhi and specified high-vehicle-density NCR districts.
Possible restrictions on certain industrial operations and brick kilns, depending on the applicable directions.
Consideration of hybrid or online schooling and work-from-home arrangements under the relevant orders.
Intensified enforcement against polluting vehicles and industrial sources.
Stage IV: Severe+ air quality
Further tightening of construction and demolition restrictions, with fewer exemptions.
Restrictions on the entry of trucks into Delhi, with specified exemptions for eligible cleaner vehicles and essential services.
Possible restrictions on certain categories of older diesel vehicles and other high-emission activities under the applicable directions.
Consideration of additional emergency measures affecting schools, offices and other activities.
Greater coordination among Delhi, neighbouring States and central agencies.
Challenges
Temporary rather than structural intervention
GRAP is activated when pollution becomes severe. It does not, by itself, permanently eliminate pollution from vehicles, industries, power generation or construction.
Regional nature of pollution
Air pollution does not respect administrative boundaries. Crop-residue burning, industrial emissions and polluted air can affect multiple NCR districts and neighbouring States, making coordinated action essential.
Weather dependency
Even when emissions are reduced, low wind speeds and temperature inversions can prevent pollutants from dispersing quickly. This makes the visible impact of emergency measures variable.
Economic and social costs
Construction bans, vehicle restrictions and workplace disruptions can affect workers, small businesses, transport operators and daily-wage earners. Poorly designed measures may impose disproportionate costs on vulnerable groups.
Way forward
Move from emergency response to year-round pollution control
Enforce emission standards even when AQI is moderate.
Strengthen industrial pollution monitoring and cleaner fuel adoption.
Improve waste management and prevent open burning.
Make dust-control compliance mandatory at construction sites.
Reform urban transport
Expand reliable buses, metro connectivity and last-mile transport.
Improve pedestrian and cycling infrastructure.
Accelerate the adoption of cleaner public and commercial vehicles.
Strengthen vehicle inspection and scrappage mechanisms.
Address agricultural pollution
Provide affordable access to crop-residue management machinery.
Promote alternative uses of paddy straw, including bioenergy and industrial applications.
Coordinate crop-residue management policies across Punjab, Haryana, Uttar Pradesh and Delhi.
Provide farmers with financial and technical incentives rather than relying only on penalties.
Strengthen scientific monitoring
Expand air-quality monitoring stations and public data access.
Use source-apportionment studies to identify the contribution of different pollution sources.
Evaluate the impact of individual GRAP measures.
Use pollution forecasts to implement preventive measures before severe pollution develops.
Protect public health
Provide timely health advisories during pollution episodes.
Improve access to clean indoor air in schools, hospitals and public facilities.
Protect outdoor workers and vulnerable populations.
Ensure that restrictions on work, transport and schooling are proportionate to the health risk and accompanied by appropriate support.
Conclusion
GRAP is a significant emergency tool to control pollution during air-quality emergencies but cannot be relied upon as a sole solution. The failure to show any continuous improvement in the winter AQI of Delhi shows that the pollution sources must be tackled throughout the year. To find a sustainable solution, there has to be a shift from restriction-oriented measures to prevention-focused regional air-quality management. Concerted efforts from transport, industrial, agricultural, dust, and burning of waste have to be made to improve air quality.



