(a) whether the Central Pollution Control Board (CPCB) has made it mandatory for several industries to use Piped Natural Gas (PNG) in order to check pollution;
(b) if so, the details thereof;
(c) whether any industry has violated the said instructions and if so, the details thereof along with the monitoring mechanisms put in place in this regard; and
(d) the number of such industries which have violated the instructions of CPCB along with the action taken thereto for non-compliance?