California could become the first US state to require new cars to be fitted with passive speed alerts which chime when a driver exceeds the speed limit, following in the tracks of Europe.

    The bill – known as California Senate Bill 961 (SB-961), and passed in the upper house last week – proposes a requirement for 50 per cent of new cars sold in the state to be fitted with a passive speed limiter by 2029, before the system becomes mandatory by 2032.

    Passive intelligent speed assistance (ISA) systems use GPS data to send the speed limit of the road a car is travelling on to its dashboard, where the posted limit is displayed.

    According to the proposed law, each time the car exceeds the posted speed limit by 10mph (16km/h), the system will set off a one-time visual and audio alert to warn drivers to slow back down – but it can’t physically slow the car down or reduce its power.

    It hasn’t yet been enacted into law, with the proposal next heading to the California State Assembly where it’ll need to be passed before August 31 to come into effect.

    While California is in line to be the first US state to introduce requirements for ISAs, the technology has been mandated in Europe since July 2022.

    In Europe, the ISA system is triggered when a car exceeds the posted speed limit by three per cent – significantly less than the blanket 10mph (16km/h) application due to be enforced in California.

    The Australian Government said back in 2019 that it was looking to introduce a requirement for ISAs in locally delivered new cars, though there are no Australian Design Rules (ADR) relevant to the safety system as yet.

    A growing number of cars sold in Australia include speed limit warnings, however many of these systems rely on speed sign recognition.

    Jordan Mulach

    Born and raised in Canberra, Jordan has worked as a full-time automotive journalist since 2021, being one of the most-published automotive news writers in Australia before joining CarExpert in 2024.

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