ExplainedEnvironment
Green crackers explained: what makes a firecracker 'green', and why Delhi gets them for just two days
On Monday the Supreme Court allowed certified green crackers in Delhi-NCR on 7 and 8 November, with the full ban back on 9 November. What these crackers are, how much cleaner they really are, and how to tell a genuine one from a fake.
The short answer
Green crackers are firecrackers made to formulas developed by the CSIR's National Environmental Engineering Research Institute (NEERI) in Nagpur. They drop barium, use less aluminium and smaller shells, and are designed to give off at least 30% less particulate matter, sulphur dioxide and nitrogen dioxide than conventional crackers. They are not pollution-free, and last Diwali Delhi's air still turned very poor. The Supreme Court has allowed them in Delhi-NCR only between 6 and 7 am and 8 and 10 pm on 7 and 8 November, sold from 4 to 6 November at approved sites, in sealed boxes with a QR code that traces the maker.
What is a green cracker?
It is a firecracker made to a cleaner recipe developed by government scientists. After the Supreme Court restricted firecrackers in the 2018 Arjun Gopal judgment and asked for less polluting alternatives, the Council of Scientific and Industrial Research (CSIR) and its National Environmental Engineering Research Institute (NEERI) in Nagpur worked out new formulations. The first green crackers reached the market in 2019.
Ordinary crackers get their colour and bang from compounds of metals such as barium, strontium and copper, which end up in the air people breathe. Green crackers leave out barium compounds altogether, cut the use of aluminium and thermite, and use potassium nitrate instead. They also have smaller shells and carry dust suppressants.
How much cleaner are they?
The design target is at least 30% less pollution: lower emissions of fine particles (PM), sulphur dioxide and nitrogen dioxide than a conventional cracker of the same kind. NEERI has three main families. SWAS releases water vapour to hold down dust and cuts particulate matter by 30 to 35%. STAR uses a modified thermite and cuts sulphur dioxide and nitrogen dioxide by 20 to 30%, with less noise. SAFAL swaps most of the aluminium for magnesium and cuts metal and particle emissions by 30 to 35%. Newer versions claim a 45 to 60% fall in PM10.
Noise falls too, but only slightly. Green crackers produce roughly 110 to 125 decibels, against up to 160 decibels for some conventional ones.
Conventional and green crackers
So why is there still a ban?
Because cleaner is not the same as clean. NEERI’s figures come from controlled tests, and the saving per cracker can vanish if people simply burst more of them. At a hearing in April 2025, Justice A S Oka said there was “nothing green about these crackers” and that the “only solution is to come up with crackers that have zero emission.”
Last year’s Diwali made the point. On 15 October 2025 a bench of Chief Justice B R Gavai and Justice K V Chandran allowed green crackers for three days, 18 to 20 October, in the same two daily time slots. The day after Diwali, Delhi’s air quality index stood at 351 at 6 pm, with 35 of 38 monitoring stations in the very poor or severe bands. The average PM2.5 level after the festival was 488 micrograms per cubic metre, the highest since 2021 and about eight times the 24-hour national standard of 60. Police registered over 175 FIRs, mostly for bursting outside the permitted hours. Climate Trends, a research group, said burning “so-called ‘green’ crackers made no measurable difference compared to regular ones.”
What has the court allowed this year?
A bench of Justices M M Sundresh and Prasanna B Varale has allowed certified green crackers in Delhi-NCR on 7 and 8 November only, from 6 to 7 am and from 8 to 10 pm. Licensed traders may sell them from 4 to 6 November, only at sites picked by district officials and police. Online sales are banned, as are joined “ladi” crackers, garlands and anything with barium. Areas within 300 metres of hospitals, schools, colleges, old-age homes and silence zones are no-cracker zones. The year-round ban returns on 9 November.
How do I know a cracker is genuinely green?
Look for the NEERI logo and a QR code on a fully sealed box. This year the court has made the code product and batch specific: scanned, it must show the manufacturer and its NEERI registration, and only products uploaded on NEERI’s website between 2 and 6 November count. NEERI’s “CSIR NEERI Green QR Code App” can read the code.
The extra checks follow a lesson from last year. The Commission for Air Quality Management found that QR codes had been sold to unregistered makers, letting ordinary crackers pass as green. Under Monday’s order, a code cannot be transferred, and selling one leads to cancellation of the licence.
Firecrackers in Delhi-NCR: how the rules got here
- 2018Supreme Court restricts firecrackers in the Arjun Gopal case and pushes for less polluting ones
- 2019First CSIR-NEERI green crackers go on sale
- 15 Oct 2025Court allows green crackers in Delhi-NCR for 18 to 20 October
- 2 Nov 2026Court allows green crackers on 7 and 8 November, sales 4 to 6 November
- 9 Nov 2026Complete ban returns; compliance hearing on 16 December
What happens after Diwali?
The court wants evidence this time. Pollution control boards must file air quality reports for 2 to 6 November, for the two festival days and for 9 to 30 November, and the case returns for compliance on 16 December. Those numbers will decide whether the two-day window is repeated, tightened or dropped next year.