Jharkhand Pollution Control Board has limited firecracker usage to 8 pm-10 pm on Diwali, with penalties for violations. While sale of low-decibel crac. While sale of low-decibel crackers is permitted in areas with good air. The noise level in Ranchi’s designated ‘silence zone’ – Old High Court – touched the 78-decibel mark on Diwali, a spike of nearly 56 per cent, while other parts of the eastern state also.