feel that the ban on selling petrol without the certificates may prove impractical and not enforceable.

Oil industry sources told Express Newsline that there exist no legal provisions to deny petrol to vehicles without PUC certificates. However, Sharad Sharma, the state level co-ordinator for the four oil companies, declined to comment on the transport commissioner's directives and said the companies would go into a meeting on Tuesday to decide on implementation of this scheme.

``The attendant at a petrol pump is often illiterate and may not even be able to verify PUC certificates,'' said a petrol pump owner from south Mumbai. Other pump dealers painted gloomy pictures of fights between attendants and vehicle owners. ``They could even end up boycotting our petrol pumps,'' said one dealer alarmed at the prospect of having to turn backhordes of motorists who don't have certificates. ``We don't want to be taking over the responsibility of the RTO,'' confessed another petrol dealer.

In its strongest set of directives to enforce the PUC certificates, the Transport Commissioner Vinay Mohan Lal said last week that from October 15, petrol in the island city, will be sold only to those vehicles with a PUC certificate. Lal has sent individual letters to dealers asking them to cooperate in the move.

However, petrol pump owners have also expressed apprehension at the cost of conducting subsidised PUC testing at their centres. ``We have been asked to conduct the tests at subsidised tests for six weeks, how will we manage?'' asks Cawas Majai, who owns a petrol pump in south Mumbai, adding that costs were already going up.

What has taken them by surprise is a recent circular from the Motor Vehicles Department (MVD) asking them to conduct PUC tests at Rs 25 instead of the earlier Rs 50.

In a significant step to reduce the harmful effects causedby the high lead control in petrol, the four major petrol companies will start selling only unleaded petrol in the 200 outlets all over the city from October 2.

Currently, leaded petrol accounts for monthly sales of over 28,262 kilolitres of leaded petrol while only 5,773 kilolitres of unleaded petrol are sold per month. Unleaded petrol was introduced in the city four years ago to reduce the carcinogenic effects of tetra ethyl lead (TEL) in petrol.

For cars with catalytic convertors, the use of ULP further decreases the release of harmful gases through the exhaust. Carbon monoxide and other hydrocarbons get converted into carbondioxide and water vapour. However, if ULP is not used in cars having a catalytic convertor, the convertor will be destroyed due to the lead content, Sharma warned.