How loud is an ambulance siren?
Measured emergency vehicle sirens in Poland produced 104 to 108 dB(A). Inside the vehicle, a Danish study found physicians riding in the back of ambulances with sirens on were exposed to 79 to 80 dB(A) on average, with brief peaks up to 123 dB(C).
- Level
- 104–108 dBAA-weighted sound level
- Daily limit
- 2 min 22 s a dayNIOSH, at the loud end
- Versus conversation
- 22,387× energyabout 20.4× as loud
What the numbers mean
How it was measured. Measured A-weighted levels of Polish emergency vehicle siren signals, 104 to 108 dB; measurement distance not given in the abstract. Inside an ambulance with sirens on, crew exposure was 79 to 80 dB(A) Leq in a Danish study.
A study of authorised emergency vehicle sirens in Poland measured A-weighted levels of 104 to 108 dB for the warning signals, and noted that the sound that informs other road users becomes annoying noise for the crew. Sirens are designed to be loudest straight ahead of the vehicle; California, for example, sets a minimum of 120 dB(A) on axis at 3 m for its top siren class.
A Danish study fitted miniature microphones beside the ear canals of physicians on emergency runs. In ambulances with sirens on, average exposure was 79 dB(A) on urban roads and 80 dB(A) on rural roads and motorways, with peaks up to 123 dB(C). An earlier study cited in the same paper found a mean of 96 dB(A) inside an ambulance cabin with sirens on. Over a whole shift the Danish physicians' average was lower, 71 dB(A), because the sirens run only part of the time.
How long is safe?
NIOSH recommends no more than 2 min 22 s a day at 108 dBA (5 min 57 s at 104). OSHA's legal limit is 40 min.
| 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 |
|---|---|---|---|---|
| 104 dBA | 5 min 57 s | 1 h 9 min | 1 min 55 s | 6 min 3 s |
| 108 dBA | 2 min 22 s | 40 min | 46 s | 2 min 24 s |
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.
Pets
Dogs often howl at passing sirens; it is a short exposure and usually harmless.
Protecting your hearing
Pedestrians should step back from the kerb as an ambulance passes. Crews can reduce exposure with closed windows and hearing protection that still allows radio communication.
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).
- Nightclub (94–112.4 dBA): this has about 1.9× its sound energy and sounds about 1.2× as loud.
- Rock concert (99.8–108 dBA): this has about 1.6× its sound energy and sounds about 1.2× as loud.
- MRI scanner (102–115.8 dBA): it has about 1.9× the sound energy of this and sounds about 1.2× as loud.
- Crying baby (99–120 dBA max): it has about 2.2× the sound energy of this and sounds about 1.3× as loud.
- Normal conversation (55–70 dBA): this has about 22,387× its energy and sounds about 20.4× as loud.
Questions
How loud is an ambulance siren?
Measured siren signals in Poland were 104 to 108 dB(A).
How loud is it inside the ambulance?
Physicians in the back of Danish ambulances with sirens on averaged 79 to 80 dB(A), with peaks to 123 dB(C).
Sources
- Occupational exposure to noise from authorized emergency vehicle sirens, International Journal of Occupational Safety and Ergonomics (Górski, 2014), abstract via Europe PMC. Supports: dB_low 104, dB_high 108 dB(A).
Measured A-weighted SPLs of those signals range between 104 and 108 dB.
Checked 2026-11-03. - Noise exposure during prehospital emergency physicians work on Mobile Emergency Care Units and Helicopter Emergency Medical Services, Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine (2017). Supports: 79 to 80 dB(A) inside ambulance.
When the physician escorts the patient to the hospital in the ambulance, exposure values of 79 dB(A), 80 dB(A) and 80 dB(A) are measured.
Checked 2026-11-03. - Noise exposure during prehospital emergency physicians work on Mobile Emergency Care Units and Helicopter Emergency Medical Services, Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine (2017). Supports: urban road peak 123 dB(C).
Ambulance urban road 88 73 79 4 123 100 108 6 26
Checked 2026-11-03. - Noise exposure during prehospital emergency physicians work on Mobile Emergency Care Units and Helicopter Emergency Medical Services, Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine (2017). Supports: 96 dB(A) earlier study.
all noise values measured inside the cabin exceeded the national occupational health regulation of 85 dB(A) as a mean of 96 dB(A) was measured
Checked 2026-11-03. - Noise exposure during prehospital emergency physicians work on Mobile Emergency Care Units and Helicopter Emergency Medical Services, Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine (2017). Supports: 71 dB(A) over a shift.
Physicians in MECU and HEMS were on average exposed to (of L eq8h ) 71 dB(A) and 73 dB(A), respectively
Checked 2026-11-03. - Cal. Code Regs. Tit. 13, § 1028 - Performance Requirements, California Code of Regulations (Legal Information Institute, Cornell). Supports: California 120 dB(A) on axis.
Sound Level, dB(A) Class A Class B 0 120 115
Checked 2026-11-03. - Cal. Code Regs. Tit. 13, § 1028 - Performance Requirements, California Code of Regulations (Legal Information Institute, Cornell). Supports: 3 m distance.
Table I. Minimum A-Weighted Sound Level at 3.0 m (9.8 ft)
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.