• Ashok Pradhan, principal secretary to the transport department of Delhi, has to take personal responsibility that each and every diesel bus on Delhi's roads from April 1, 2001 is plying because a new CNG bus or conversion has already been ordered to replace it. A sticker, signed by Pradhan, has to be displayed on the windscreen of the bus.

• If a bus plies on the road without an assurance of a firm order for a CNG bus or conversion, it would amount to contempt of court and Pradhan can be put behind bars. Pradhan said he would require the help of other agencies. The court said: "You can take help from anyone you like. But you will be responsible to us.'

• Schools that have placed orders for CNG buses by March 31, 2001 can ply diesel buses till September 30, 2001 provided orders have been placed for an equal number of CNG conversions or new CNG buses. The Delhi Transport Corporation (DTC) will continue to supply buses to government schools which have poorer students.

• As DTC has placed orders for 1,880 buses, it can ply as many diesel buses till September 30, provided these are not more than eight years old.

• Private operators with buses that have an all India tourist permit can ply these till September 30, 2001, provided the buses are not more than eight years old.

• No commercial vehicle will be registered in Delhi that don't conform to the order dated July 28, 1998. This is in response to the Delhi transport department registering thousands of diesel buses even after the July 28, 1998 Supreme Court order.

• The transport department shall take steps to ensure that there is no misuse or abuse of the relaxations given by the court.

• The Environmental Pollution (Prevention and Control) Authority has been directed to examine if ultra-low sulphur diesel (ULSD), with sulphur content of not more than 0.001 per cent, can be called clean fuel.