Are Delhi residents exposed to lesser particle number concentration due to the firework ban in the city?

Diwali, the fireworks festival of India, adds more atmospheric particles within a short period of time and deteriorates the air quality. Short-term policies like banning crackers during fireworks festivals can help improve urban air quality. The present study analyzed particle number concentration, ranging from 10 to 1000 nm, in 2021 and 2022. A reduction in the concentration of particle number concentration (from 3.8 × 10⁴ cm⁻³ to 3.1 × 10⁴ cm⁻³) was observed due to the ban on crackers in the urban city of Delhi. The concentration range changes from 10⁵ cm⁻³ to 10⁴ cm⁻³. The contribution of different size ranges, Nucleation (10 to 30 nm), Aitken (30 to 100 nm), and Accumulation (100 to 1000 nm) are analyzed.  During Diwali day, the Accumulation mode particles contribute to around 60% to 83% to the total particle number concentration. The exposure to total inhalable particle concentration on Diwali (During ban on firecrackers) was reduced by about 18%, i.e., 1.6 million particles per day. The study results show that emissions in urban regions can be reduced significantly by proper implementation of policy and participation from citizens. Reducing particle emissions paves the way for air quality improvement, health impact mitigation, and sustainability. Sustainability goals focus on clean air for all, and health improvement in polluted regions as interim goals, that can be achieved by implementing proper mitigation measures, which consequently help fight climate change.