A recent two-day blitz on pollution-producing road vehicles saw Renfrewshire Council catching seven offenders.
Enforcement officers from Renfrewshire and neighbouring councils took to the streets in Paisley to check whether vehicle emissions were within UK legal limits.
It is an offence under UK law to drive a vehicle on the road which operates above permissible levels for exhaust emissions.
Of the 273 vehicles tested, seven failed and were issued with £60 fixed-penalty notices.
45 of the vehicles that were tested were private hire taxis. Of the 32 Renfrewshire taxis that were tested, four failed the test, resulting in immediate suspension of licences and a £60 fixed penalty.
Six East Renfrewshire taxis and seven Glasgow City taxis were also tested, with no failures.
The tests were carried out in Paisley town centre on 28 and 29 October in partnership with officers from Police Scotland, who were responsible for pulling over the vehicles from traffic.
Councillor Eddie Devine, convener of Renfrewshire Council’s Environment Policy Board, said: “These tests are carried out regularly to ensure that drivers are complying with the law.
“Checking vehicle emissions is an important part of the work that the council does to protect Renfrewshire’s environment.”
Fixed penalty notices will be waived if drivers provide evidence within fourteen days that their vehicle has been retested and complies with the emissions legislation.
The police also detected a number of minor road offences during the testing, including tyre defects and accident damage.
One driver received a police warning for aggressive behaviour.
The drivers of all the tested vehicles were given a copy of Renfrewshire Council’s “Don`t be an Idler” information leaflet explaining the environmental problems caused by vehicle idling.
Exhaust fumes contain a range of air pollutants such as carbon monoxide, nitrogen dioxide, hydrocarbons and particulates.
Emissions of these pollutants are regulated by UK emissions standards.