California to target loud cars with clever cameras

The US state of California is set to become the latest jurisdiction to install cameras and sensors to detect cars with loud exhausts.

Fines will be issued in the same way speed camera tickets are subsequently sent to the registered vehicle owners by mail, after an offence has been detected.

As reported by US publication Autoweek, California legislators have approved a pilot program to detect cars that breach the state's noise limits.

The trial is due to start from next year for five years, across six California cities.

California government documents reportedly describe "sound-activated enforcement devices" which activate when "noise levels have exceeded the legal sound limit" and "obtain clear video of a vehicle and its (registration) plate".

These devices will record audio and video of traffic in both directions for the road they're installed on, and automatically save footage of offending vehicles for manual review at a later date.

Fines will not be issued the first time a vehicle passes under one of the sound devices, rather from the second instance onwards, according to the report by Autoweek.

The cost of the fine for excessively loud vehicles is yet to be announced.

It is also unclear how noise from specific vehicles will be pinpointed in traffic.

Current California law states a noise limit of 95 decibels for motor vehicles with gross vehicle masses (GVM) below 6000lb (2722kg) – which includes most passenger cars and SUVs.

However, this weight threshold excludes heavier vehicles such as pick-ups, including the best-selling vehicle in the US, the Ford F-150.

Motorcycles built after 1985 carry a noise limit of 80dB, the publication reports. It's unclear how the new noise sensors and cameras will differentiate between cars and motorcycles.

According to Autoweek, signs will notify motorists they're approaching one of the sound-detecting devices.

The trial is set to run for five years – from January 2023 to the end of 2027 – across six cities, with the exact locations to be decided though a "public input process".

California is not the first jurisdiction to implement cameras and sensors to detect noisy cars. Similar systems are in place elsewhere in the US, and are under consideration in the UK and France.

In Australia, the New South Wales government installed a noise camera on the south coast in 2009 – to detect trucks with excessive brake noise, rather than to catch cars with loud exhausts.

However, the NSW south coast noise camera did not issued a single fine. Legislation was not passed to allow camera-detected excessive truck brake noise offences to be enforced.

The NSW south coast noise camera was operated in 2009 and 2010 to test its accuracy, and then used to help develop a standard for excessive brake noise in 2013 – before being switched off, according to local newspaper, the Illawarra Mercury.

Noise detection camera technology in New York – trialled for nine months from September 2021 – is said to be similar to the system planned for California.

Drive reported in February 2022 the New York owner of a BMW M3 was issued a $US875 fine if they refused to rectify their vehicle's non-compliant exhaust, after the cars was flagged by the cameras.

Similar programs are being trialled – or under consideration – in Tennessee, USA, as well as Paris, and the UK.