Thiruvananthapuram: The National Green Tribunal, in a bid to curb excessive honking, has directed the Delhi road transport department to measure decibel levels of pressure horns installed on vehicles while issuing pollution under control (PUC) certificates.

The order was passed by the tribunal while directing the Delhi road transport department and traffic police to check and prohibit the entry of heavy vehicles that have pressure horns. The green order comes following a Public Interest Litigation on noise pollution filed by the Supreme Court Group Housing Society and Indian Foreign Service Group Housing Society in the Delhi high court. The case was later transferred to the National Green Tribunal.