The story so far: Last October, in a landmark judgment, the Supreme Court of India mandated the use of green crackers for Deepavali, prescribing specific norms for the manufacture. This year, for the first time, ‘green crackers’ have been made available in markets, though the reach has been limited. These are milder avatars of traditional firecrackers in terms of the sound and smoke generated when burnt. The Supreme Court had banned the use of barium nitrate, a key pollutant in crackers. The National Environmental Engineering Research Institute (NEERI), a part of the Council of Scientific and Industrial Research (CSIR), was asked to facilitate the development of green crackers.
What are green crackers?
Traditionally, firecrackers have been made with barium nitrate, antimony and a range of metals that, over the years, have been linked to respiratory diseases and even cancer.
These were the factors that guided the Supreme Court when it decided to ban fireworks. The ban last October came on the basis of a petition filed in 2015, by a few infants through their parents. They said air pollution caused by various factors, especially firecrackers, made Delhi a gas chamber. Months before the ban, a group of research institutes of the CSIR had begun work on ‘green crackers,’ namely fireworks without barium nitrate. The mainstay of the cracker manufacturing process, barium nitrate lends itself to making explosives that are effective and convenient. The Nagpur-based NEERI eventually hit upon formulations that substituted barium nitrate with potassium nitrate and zeolite. The ‘green’ versions of the ‘flower pot’, one of the most popular fireworks, has a mixture of water and lime that is chemically stored in the cracker. When lit, the effulgence also triggers water and the makers claim that the moisture wets the dust-and-smoke particles.
NEERI claims that tests in its laboratories have seen a reduction of nearly 30% in particulate matter (PM) and also reduced a release of sulphur dioxide and nitrous oxide emissions.
Green sparklers use 32% potassium nitrate, 40% aluminium powder, 11% aluminium chips, and 17% “proprietary additives” to reduce particulate matter PM10 and PM2.5 to 30%.
Similarly, a new formulation of a ‘bomb’ named ‘SWAS’ (or safe water releaser) uses 72% of a “proprietary additive”, 16% potassium nitrate oxidiser, 9% aluminium powder, and 3% sulphur to reduce PM10 and PM2.5. On its website, NEERI claims that green crackers when exploded also emit similar levels of sound (100-10dBA) associated with traditional crackers.
NEERI has signed agreements with 230 companies to manufacture and make them available for sale. This was also preceded by setting up demonstrations in Sivakasi, Tamil Nadu, where about 90% of India’s crackers are manufactured.
What about supplies?
Firecracker manufacturers are still nervous about how acceptable the green crackers will be in the market; several say they have not yet adopted it. The ban on crackers since last year has meant a shortage of unskilled labour — the mainstay of the industry — and several manufacturers got the legal go-ahead to make the crackers only in May. The manufacturers said this did not give them enough time to make and supply crackers across the country for Deepavali. Fireworks manufacturers were also hopeful of legal clarity on a sub-category of green crackers called “improved crackers”. This version continues to use barium nitrate but in extremely reduced amounts; when its explodes, harmful chemicals do not spray as much as earlier into the air. These improved formulations, as they are categorised, are preferred by manufacturers because barium is a tested workhorse. The Supreme Court is yet to take a decision on whether to allow them. Market reports suggest that consumers are not finding it easy to buy crackers. Retailers say stocks are low and there is only a limited selection of firecrackers available. The size of the cracker market is reportedly valued at around ₹1,800 crore and is expected to take a severe hit this year. Those who deal with crackers say that 2019 is a transition year and that by next year, supply chains will adapt better to ensure that green crackers are available more easily.
Are green crackers less polluting? What could it be like this year?
Green cracker manufacturers claim that particulate matter pollution will be reduced by 30% if these crackers are used. However, these numbers have been computed in a laboratory setting and not been verified in real world conditions.
Because green crackers are not available in sufficient numbers this year, any reduction in smoke levels cannot entirely be attributable to the improvements in crackers themselves.
Last year in spite of the ban, revellers burst crackers wantonly, particularly in Delhi and surrounding satellite towns. The morning after Deepavali, saw the city waking up to a blanket of smog and having air quality plummeting to nearly 574 — on the Air Quality Index (AQI), this registers as “Severe+” and triggers emergency action according to the Graded Response Action Plan (GRAP). GRAP is the city’s five-step escalating plan to counter air pollution.
Various directives of the GRAP kick in based on the recommendation of a committee of experts; these include steps such as declaring a holiday in schools to banning construction activity. The onset of winter has caused air quality in Delhi to dip to ‘very poor’ and this has already triggered some GRAP restrictions on crackers. Any additional load of crackers will only cause air quality to further deteriorate. SAFAR, or System of Air Quality and Weather Forecasting, which is an air quality and weather forecast system, warns that the highest impact of fire cracker emissions is expected early morning on October 28 (1 a.m.-6 a.m.). Some part of Delhi’s poor air is due to stubble burning in Punjab and Haryana.
Even if no crackers are lit, air quality would remain in the ‘very poor’ category during Deepavali (October 27-28). However, if even 50% of the total load of fire crackers (compared to the average of Deepavali-2017 and 2018) is added, the AQI may cross into the “severe” category for a short period but with a relatively much less magnitude than last year. Relatively favourable wind conditions now when compared to last Deepavali, which fell in November, would mean that the extra burden from crackers would be ‘air flushed out’ within a few days unlike last year when it persisted for several days.