Delhi struggles with enforcement, violations of time, ‘green’ firecracker curbs worsen pollution

Green firecrackers are modified fireworks intended to emit less pollution than conventional ones. The Supreme Court allowed only improved and green firecrackers without barium salts, which colour flames and supply oxygen for fuel. Their importance comes from reducing, not eliminating, emissions.

CSIR-NEERI developed designs including SWAS after the 2018 court order. These designs replaced barium nitrate with zeolites, reduced aluminium, and added dust suppressants. Some also removed potassium nitrate and sulphur. Government estimates said particulate matter could fall by 30–40%, while CSIR-NEERI claimed a 30–35% reduction compared with traditional fireworks.

The reductions apply mainly to particulate matter, and green crackers still burn metal salts for colour. Experts therefore say they still release substantial particulate matter, sulphur dioxide, and nitrogen oxides. Calling a firecracker green does not make it pollution free, especially when many are used together.

The Supreme Court permitted green firecrackers in Delhi-NCR during two narrow windows: 6am to 7am and 8pm to 10pm. The allowance applied for two days ahead of Diwali. Outside those hours, the restrictions were intended to prevent prolonged bursts of pollution during already hazardous air-quality conditions.

In practice, the order was widely flouted. Fireworks continued well past midnight, even though a complete ban had taken effect. Sunil Dahiya reported that most of the sharp increase in sulphur dioxide came after the 10pm deadline. Hourly PM2.5 later peaked around 1am, showing that pollution continued during prohibited hours.

The episode exposed a gap between court rules and enforcement. Police patrols and restrictions existed on paper, but implementation remained lax. Neighbourhoods were left under a thick haze, while authorities struggled to establish whether the fireworks being used were genuinely green or conventional.

Delhi’s hourly PM2.5 concentration peaked at nearly 600 micrograms per cubic metre around 1am on Diwali night. The Central Pollution Control Board data cited in the article put that level at more than ten times the 24-hour standard of 60 µg/m³. The comparison shows how sharply pollution surged during the celebrations.

PM2.5 consists of very fine airborne particles, and the article uses it as a key measure of the pollution episode. Fireworks added a sizeable load of fine particles to stubble smoke trapped close to the ground. The increase was not limited to the permitted period, because much of the sulphur dioxide rise occurred after 10pm.

The peak occurred while Delhi was already struggling with hazardous air quality. Light easterly winds kept stubble smoke out of the city that night, but fireworks still drove sulphur dioxide sharply upward. The result was a thick haze across neighbourhoods and little practical relief from the restrictions.

Green firecrackers are a partial reduction measure, not a pollution-free substitute. Experts said their lower emissions could reduce peak pollution somewhat, but they still produce substantial particulate matter, sulphur dioxide, and nitrogen oxides. Delhi’s air was already overloaded, so even a smaller contribution mattered.

The article gives two linked problems. First, the claimed reduction applies mainly to particulate matter, with estimates around 30–35% or 30–40%. Second, authorities could not reliably separate green products from conventional ones. Fireworks continued beyond the permitted hours, and most of the sulphur dioxide increase came after the 10pm deadline.

Large-scale use magnified the remaining pollution. Green crackers still emit 65–70% of traditional firecracker pollution, so a 30% per-unit reduction remains substantial when millions are burst. Experts called for stronger action against other pollution sources and, in one view, an end to festival firecracker bursting.

The government said green firecracker designs cut particulate matter by 30–40%. CSIR-NEERI claimed a 30–35% reduction compared with traditional firecrackers, while the Supreme Court expected at least a 25–30% cut in PM2.5 emissions. These figures describe reductions, not the complete removal of pollution.

The key mechanism is cumulative use. A green firecracker may emit less than a conventional one, but it still releases substantial particulate matter, sulphur dioxide, and nitrogen oxides. The article estimates that green fireworks retain 65–70% of traditional firecracker pollution. The cuts also apply to particulate matter, rather than every pollutant equally.

When millions of firecrackers are burst, the remaining emissions accumulate rapidly. As Sunil Dahiya put it, 30% less of a very large amount is still a very large amount. That is why experts described the overall reduction as negligible in Delhi’s already polluted air.

Weak enforcement undermined the entire green-firecracker policy. The Supreme Court required product-specific QR codes, designated sale locations, and police patrol teams to stop conventional crackers from being sold or used. These measures depended on checks that could identify products and control where they were distributed.

That system did not work effectively on the ground. IIT Delhi professor Mukesh Khare said the distribution network was poor, with too few outlets selling green firecrackers. He said conventional crackers could therefore flood markets, while there were no adequate checks and balances. Environmental activist Bhavreen Kandhari also reported illegal fireworks to Delhi Police in recent years.

The result was uncertainty over what people actually burst. Authorities did not establish whether fireworks were green or conventional, and restrictions were widely ignored. Without verification, enough green products, and consistent policing, the legal distinction offered little protection from pollution.

Weather determines how quickly pollution can disperse. When smoke is trapped close to the ground, fine particles and gases remain where people live and breathe instead of moving away. The article describes a sizeable load of fine particles on top of stubble smoke trapped near the ground, creating conditions for a thick haze.

Fireworks then add more pollutants to that concentrated air. Sunil Dahiya said sulphur dioxide rose about 40% the day before Diwali and nearly quadrupled during the relevant period. Most of that increase came after the 10pm deadline. Environmental activist Bhavreen Kandhari said green crackers also pollute Delhi’s already saturated air when meteorological conditions are highly unfavourable.

The article notes that light easterly winds kept stubble smoke out of the city, but they did not prevent fireworks from sharply raising sulphur dioxide. The wider lesson is that even lower-emission fireworks can create dangerous peaks when pollution cannot disperse.