Trials of checking vehicular emission by remote sensing devices have started in Delhi and NCR, a move which experts said could allow efficient screening of highly polluting vehicles.

The technology is being tested at the Manesar-based International Centre for Automotive Technology (ICAT). At least 70,000 vehicles in Delhi and NCR towns have already been checked, the Supreme Court-appointed body Environment Pollution (Prevention and Control) Authority was informed.

“In response to EPCA recommendations, the Supreme Court had in May 2018 directed the Delhi government to look into the implementation of remote sensing technology for screening polluting vehicles. A report would be submitted to the apex court soon,” said Sunita Narain, EPCA member.

A senior official from ICAT explained that in remote sensing there is a light source and a detector that is placed on the side of the road. It transmits a laser beam. Emissions are measured when vehicles cross the light path. Scientists have been able to measure exhaust plume, nitric oxide, carbon monoxide, hydrocarbons and carbon monoxide in 0.5 seconds. Several vehicles can be tested in an hour by the use of this technology, the official said.

“A camera captures the image of the vehicle’s number plate which, if connected with a vehicle registration database, can identify the make, model, certified emission standard, fuel type, rated power and other details,” said the ICAT official, who didn’t wish to be named.

Experts said the Pollution Under Control (PUC) certificate regime was designed for older technologies. It is proves ineffective while screening advanced emissions control systems.

“In a scenario where only 23% of Delhi’s vehicles turn up for PUC tests and escape the legal net of scrutiny, remote sensing can capture them to get screened more efficiently in a non-intrusive manner. In a single day, remote sensing can check thousands of vehicles—several times the capacity of what PUC systems can do,” said Anumita Roychowdhury, executive director (research and advocacy) at Centre for Science and Environment.

While monitoring of vehicular emission through remote sensing is already being done in countries such as China, USA, UK and Hong Kong, in India it is in practice in Kolkata.

First Published: Jan 16, 2019 14:37 IST