How loud is an electric car?
Electric and hybrid cars must play an artificial warning sound at low speed. Under UN Regulation 138 the whole vehicle must emit at least 50 dB(A) at 10 km/h and 56 dB(A) at 20 km/h, and the system may not push the overall level above 75 dB(A), measured 2 m from the car.
- Level
- 50–75 dBAA-weighted sound level
- Distance
- 2 m2 m from the vehicle
- Daily limit
- No daily limitNIOSH, at the loud end
- Versus conversation
- 1× energyabout 1.0× as loud
What the numbers mean
How it was measured. UN Regulation 138 (series 01) for Acoustic Vehicle Alerting Systems: minimum overall 50 dB(A) at 10 km/h, 56 dB(A) at 20 km/h, 47 dB(A) reversing; maximum 75 dB(A) driving forward. The 75 dB(A) figure is at 2 m, equivalent to 66 dB(A) at 7.5 m.
Below about 20 km/h an electric motor makes little noise and tyre noise is low, so pedestrians, especially people with sight loss, may not hear an electric car coming. EU rules require an Acoustic Vehicle Alerting System (AVAS) that generates sound from start-up to approximately 20 km/h and when reversing, and refer to UN Regulation 138 for the levels.
The regulation sets minimum overall levels of 50 dB(A) at a constant 10 km/h, 56 dB(A) at 20 km/h and 47 dB(A) when reversing, plus minimums in individual one-third-octave frequency bands. It also caps the overall level with AVAS at 75 dB(A) when driving forward. A note in the regulation explains that 75 dB(A) at 2 m corresponds to 66 dB(A) at 7.5 m.
For comparison, EU type-approval limits for the noise of ordinary passenger cars in the standard pass-by test, measured 7.5 m from the track, are 72 dB(A) in phase 1 falling to 68 dB(A) in phase 3 for most cars.
How long is safe?
Below 85 dBA, the level NIOSH allows for a full 8-hour day.
| Level | NIOSH limit (85 dBA, 3 dB rule) | OSHA limit (90 dBA, 5 dB rule) | UK/EU 80 dB(A) action value reached after | UK/EU 85 dB(A) action value reached after |
|---|---|---|---|---|
| 75 dBA | No limit | No limit | Not reached in 24 h | Not reached in 24 h |
Times are for a whole day’s exposure, with the rest of the day quiet. The workplace limits were written for adults at work, not for children. Work out a mixed day with the noise dose calculator.
Protecting your hearing
There is no hearing risk at these levels. If you are a pedestrian, do not rely on hearing traffic in car parks and quiet streets; look as well, because the warning sound is deliberately modest.
Earplug and earmuff ratings (NRR in the US, SNR in the UK and EU) are lab figures; real-world protection is usually lower. How to read the ratings.
Compared with sounds nearby
Using midpoints of each range. Energy multiplies by 10 every 10 dB; perceived loudness roughly doubles (why).
- Microwave oven (55–59 dBA): this has about 3.5× its sound energy and sounds about 1.5× as loud.
- Neonatal intensive care unit (55–63 dBA): this has about 2.2× its sound energy and sounds about 1.3× as loud.
- Operating theatre (53–78.8 dBA): it has about 2.2× the sound energy of this and sounds about 1.3× as loud.
- Infant sleep machine (50–85 dBA): it has about 3.2× the sound energy of this and sounds about 1.4× as loud.
Questions
Do electric cars have to make a noise?
Yes, at low speed. EU rules require a warning sound from start-up to approximately 20 km/h and when reversing, at levels set by UN Regulation 138.
How loud is the electric car warning sound?
At least 50 dB(A) at 10 km/h and 56 dB(A) at 20 km/h, and no more than 75 dB(A), measured 2 m from the car.
Are electric cars quieter than petrol cars?
At low speed, yes, which is why the warning sound exists. Petrol cars face pass-by limits of 72 dB(A) falling to 68 dB(A) at 7.5 m in EU type approval.
Sources
- Vehicle Standard (Australian Design Rule 113/00 - Acoustic Vehicle Alerting Systems for Quiet Road Transport Vehicles) 2024, Appendix A: UN R138/01, Australian Government, Federal Register of Legislation. Supports: dB_low 50 dB(A) at 10 km/h; 56 at 20 km/h; 47 reversing.
Overall 50 56 47
Checked 2026-11-03. - Vehicle Standard (Australian Design Rule 113/00 - Acoustic Vehicle Alerting Systems for Quiet Road Transport Vehicles) 2024, Appendix A: UN R138/01, Australian Government, Federal Register of Legislation. Supports: dB_high 75 dB(A).
shall not emit an overall sound level of more than 75 dB(A), if driving in forward direction
Checked 2026-11-03. - Vehicle Standard (Australian Design Rule 113/00 - Acoustic Vehicle Alerting Systems for Quiet Road Transport Vehicles) 2024, Appendix A: UN R138/01, Australian Government, Federal Register of Legislation. Supports: 2 m distance; 66 dB(A) at 7.5 m.
The maximum overall sound pressure level of 75 dB(A) measured at a distance of 2 m is corresponding to the overall sound pressure level of 66 dB(A) measured at a distance of 7.5 m.
Checked 2026-11-03. - Regulation (EU) No 540/2014, Annex VIII (Acoustic Vehicle Alerting Systems), legislation.gov.uk (UK National Archives). Supports: speed range.
The AVAS shall automatically generate a sound in the minimum range of vehicle speed from start up to approximately 20 km/h and during reversing.
Checked 2026-11-03. - Regulation (EU) No 540/2014, Annex III: Limit values, legislation.gov.uk (UK National Archives). Supports: petrol car pass-by limits 72/70/68 dB(A).
power to mass ratio ≤ 120 kW/1 000 kg 72 a 70 a 68 a
Checked 2026-11-03. - Regulation (EU) No 540/2014, Annex II: Methods and instruments for measuring the noise made by motor vehicles, legislation.gov.uk (UK National Archives). Supports: pass-by test distance 7.5 m.
The microphone shall be located at a distance of 7,5 m ± 0,05 m from the reference line CC' of the track and 1,2 m ± 0,02 m above the ground.
Checked 2026-11-03.
This page is general information, not medical advice. If you have ringing in your ears, muffled hearing or any change in your hearing, see an audiologist or your doctor.