The city’s “frail” auto emission testing centres need to upgrade their machines in the wake of BS VI vehicles making it to the roads from April, air pollution specialists said on Thursday.

Bharat Stage VI vehicles will not require any pollution monitoring for a year, though.

BS VI vehicles will be a major boon for the city as the fuel they will use will have a sulphur content five times lower than BS IV vehicles, Anumita Roy Choudhury, air pollution expert of the Centre for Science and Environment in Delhi, said. “Their emission quality is expected to improve 80-90 per cent over BS IV vehicles,” she said. “But to sustain such emission quality, the pollution testing centres need to be strengthened.”

She spoke to The Telegraph on the sidelines of a meeting on BS VI vehicles, organised by CSE in association with the state transport department.

“The emission measuring system in auto emission testing centres will have to be upgraded to a large extent; not only more sophisticated machines will be required, but also the manpower at such centres will need an upgrade so that they can physically verify certain inbuilt pollution control systems in vehicles,” she said.

“We expect a smooth transition from BS IV to BS VI... as a pollution check on such vehicles will be required after a year; so, it is expected that a proper system will be in place by that time,” a state transport department official said at the meeting.

Transport officials and cops present at the meeting said it would be a “huge challenge”. “The link to the central server has reduced the malpractice of tampering with emission results to an extent but pollution testing centres make plenty of mistakes, either by design or because of sheer lack of knowledge,” a police officer said.

“We will look at the technical aspect of testing centres, particularly the calibration of machines,” Kalyan Rudra, chairman of the state pollution control board, said.

In effect it means the onus will be on the transport department to look into the other aspects.

While Calcutta has 72 such centres, there are 30 more in adjoining areas. “We are still unclear about the emission of BS VI vehicles,” Surojit Koley, a representative of emission testing centres in the city said.