The Sumo rolls into the pump near the Shyambazar five-point crossing for an emission check. "It will not pass, sir," opines the mechanic. "That's why we have come here," we say.

"Sure, but you will have to pay Rs 250 (instead of the card rate of Rs 100)," he retorts.

Bargaining brings it down to Rs 150. Deal struck, the mechanic gets down to business.

The oil temperature and the photograph of the number plate are fed into the `foolproof' computer and the pre-set result -- 42 HSU (passed with Grade A) -- is produced on a certificate, WB-01-0209748.

Signed and sealed in eight minutes.

Pollution Pit Stop II

Thursday, 1.30 pm, Sen Service Station, on Salkia School Road, Howrah.

The Sumo hits the pump near Golabari police station. Taxi drivers in the area have recommended this Howrah centre for a "hassle-free" pollution check.

Park, pay up, pass the test -- there's no time to waste, too many polluting vehicles to be pronounced roadworthy.

"You don't need to start the car. Just give us the bluebook details and the money (Rs 100) while we photograph the number plate," says the attendant.

The vital statistics of some previous Ambassador -- now made into a template -- is used for the Sumo. So, the speedometer reading shows 65,213 km instead of the actual 4,240 km and the test time reads 8 am instead of 1.30 pm. Another Grade A (certificate number WB-01-0205475), with 42 HSU, in five minutes flat.

Pollution Pit Stop III

Thursday, 2.30 pm, Surya Filling Station, in Bagbazar.

The PUC centre is asked to carry out the emission check "properly" -- from oil temperature to tailpipe emission.

All six emission recordings are well above the 65 HSU limit, with 67.4 being the minimum and 89.1 the maximum. The average is 79.7 HSU in the emission Test ID RAVL000178.

So, the Sumo that had passed the previous two pollution tests in the past three hours, is `FAILED'.

Official reactions

We were under the impression that the method was foolproof

-- Shyamal Sarkar, member-secretary, West Bengal Pollution Control Board.

I had no idea the computerised checking system could be manipulated

--Asim Banerjee, secretary, Auto Emission Testing Association.

If this is the case, the entire exercise becomes worthless