12Sounds made on purpose: crosswalk beeps, EV hums and station jingles

The short version: Some city sounds are designed, specified and tested so that someone can act on them without looking. In the US, accessible pedestrian signals tick once a second to help blind pedestrians find the push button and switch to a rapid tick or a spoken message when it is time to walk. Electric cars must play an artificial sound at low speed - up to 30 km/h (18.6 mph) under the US rule, about 20 km/h under the EU and UN rule - and Japan's stations and crossings have turned the same job into short melodies.

Why do crosswalks make a machine gun sound?

What you hear: a slow, quiet tock once a second while you wait, then a burst of fast clicking when the walk sign comes on.

That fast clicking is the rapid tick, the walk indication on an accessible pedestrian signal (APS)²¹³. An APS gives blind and low-vision pedestrians the same information sighted people get from the walk symbol, and in the US its behavior is set by the federal Manual on Uniform Traffic Control Devices (MUTCD). Per an orientation and mobility specialist's summary of the 2009 edition, an APS has three main sounds²¹⁴:

The locator tone lasts 0.15 seconds at most, and the signals are "intended to be loud enough to be heard only at the beginning of the crosswalk"²¹⁵. Volume adjusts automatically to the noise around the pole, so the same signal is louder at rush hour than at 3 a.m.²¹⁴

Older US signals used a cuckoo for north-south crossings and a chirp for east-west. They worked poorly: a pedestrian had to know which compass direction they were facing, and mockingbirds could imitate them, according to KQED²¹³. San Francisco had 283 APS intersections as of KQED's January 2020 reporting²¹³. For the hardware inside the push button, see Street Code's guide to crosswalk signal gear.

In the 2009 edition of the MUTCD, APS rules sat in Chapter 4E, with the locator tone in Section 4E.12²¹⁶; the current 11th edition (2023) puts them in Chapter 4K²¹⁷. California's 2026 manual, which adopts the 2023 federal edition with state amendments, lays out that chapter - including 4K.03, Walk Indications, and 4K.04, Vibrotactile Arrows and Locator Tones.

Under that text, walk tones and locator tones should be no more than 5 dBA louder than ambient sound; automatic volume adjustment is required up to a maximum of 100 dBA; tone walk indications repeat at eight to ten ticks per second; and locator tones should be audible 6 to 12 feet from the push button²¹⁸. The often-quoted 89 dBA maximum does not appear in that text.

What does the beeping at a crosswalk mean?

What you hear: a steady beep or tock from the push-button box, even when nobody is crossing.

Usually it is the locator tone, which repeats once per second throughout the "don't walk" phase²¹⁴. It is not a warning and does not mean the light is about to change. It is a beacon, kept quiet enough to be heard near the pole²¹⁵. When the walk phase starts, the sound changes character - to the rapid tick or the speech message - and that change is the signal to go²¹⁴.

Why do crossings in Japan play bird songs and music?

What you hear: a two-note "beep-boop" or a "piyo" chirp at a Tokyo crossing, or a few bars of a children's song.

Japan's accessible signals mostly use bird chirps or melodies, and municipalities choose the sounds. In the count reported by walkinginfo.org, about 10,570 of roughly 170,000 signalized intersections had APS - a dated figure - and the signals were usually switched off at 8 p.m. because of noise complaints²¹⁹. In Tokyo, Metropolis describes a "beep-boop" for east-west crossings and a "piyo" for north-south, and the nursery song "Toryanse" is sometimes heard at crossings¹¹¹.

The trade-off is visible here. Melodies are pleasant and distinctive, but direction-coded sounds rely on the listener knowing which way is which - the same problem that retired the US cuckoo and chirp²¹³.

What is the "tick-tock" and "kapow" at Australian crossings?

What you hear: a slow chirp while you wait, an urgent "tick-tock-tick-tock" to cross, and a single "kapow" when the signal changes.

That is the PB/5 pedestrian push button, designed in Australia in 1984 by a team of David Wood, Louis Challis and Frank Hulscher²²⁰. The slow chirp is its locator; the rapid "tick-tock" means cross; the "kapow" marks the change of state. A built-in microphone tracks traffic noise and adjusts the volume²²⁰. It is used in Australia, Ireland, New Zealand, Singapore and the US²²⁰.

Why do electric cars make a sound at low speed?

What you hear: a soft, rising whir or synthetic hum from an electric car pulling out of a parking space, which fades as it speeds up.

At low speed an electric or hybrid car makes far less noise than a combustion car, so governments require an artificial warning sound. In the US the rule is Federal Motor Vehicle Safety Standard (FMVSS) 141, which grew out of the Pedestrian Safety Enhancement Act of 2010²²¹. In rulemaking, NHTSA cited a study in which hybrids had a pedestrian crash rate 1.18 times that of conventional vehicles²²¹.

FMVSS 141 requires sound when the vehicle is stationary but not in Park, in reverse, and moving forward up to 30 km/h (18.6 mph)²²¹. The rule phased in with 50% of production by September 1, 2019 and full compliance by September 1, 2020²²¹. Under one of the compliance options, sounds that meet the standard at 30 km/h measure roughly 60 to 64 dBA overall²²¹.

In Europe the device is called an Acoustic Vehicle Alerting System (AVAS). EU Regulation 540/2014, Article 8, required AVAS on new types of hybrid and pure electric vehicles from July 1, 2019 and on all new ones from July 1, 2021²²². AVAS sounds up to about 20 km/h and in reverse²²³.

The UN test, UN Regulation 138, places microphones 2 m from the vehicle center line. Forward sound at 10 and 20 km/h must not exceed 75 dBA, and the pitch must rise by at least 0.8% per km/h on average, so the sound itself tells you the car is speeding up²²⁴. China's GB/T 37153 mirrors R138 with minimum levels 2 dB higher²²⁴.

The minimum levels in R138, as published in the EU's Official Journal in January 2017, are 50 dBA at a constant 10 km/h, 56 dBA at 20 km/h and 47 dBA in reverse²²⁵. Japan's transport ministry issued guidelines for these devices in January 2010²²⁶. The ministry's guideline text calls for a device that sounds automatically from starting up to 20 km/h and in reverse, with a continuous sound that suggests a running vehicle; sirens, chimes, melodies and animal calls are listed as unsuitable, and a driver-operated pause switch is allowed²²⁷.

At what speed does an electric car's warning sound turn off?

Above the crossover speed - the point where tire-on-road noise (see Traffic) becomes loud enough to do the job - the artificial sound is no longer required. The two main rules draw that line in different places: 30 km/h (18.6 mph) in the US and about 20 km/h in the EU²²¹²²³. NHTSA considered lowering the US crossover to 20 km/h and declined; the National Federation of the Blind backed keeping it at 30 km/h²²¹. The US rule also requires sound when the car is stopped in gear, which the EU summary does not mention²²¹²²³.

The same idea is reaching heavy vehicles. When New York City's Sanitation Department piloted a Mack LR Electric refuse truck from November 2020, the truck was described as "near-zero" noise, with white noise added so people nearby would know it was there¹⁴².

What is the little tune before a train leaves in Japan?

What you hear: a cheerful jingle of about seven seconds on the platform, right before the doors close.

That is a hassha melody (departure melody). Japanese railways adopted melodies partly as noise reduction and passenger service, because the metal bells used by Japanese National Railways were unpopular²²⁸. Early examples include Bungo-Taketa Station, which played "Kojo no Tsuki" from a 1951 record, and the Keihan railway, which began a melody in August 1971. After privatization, Sendai became the first JR East station with melodies on November 22, 1988, and Shinjuku and Shibuya followed on March 11, 1989. About seven seconds is considered the ideal length²²⁸.

Some stations have signature tunes: Ebisu plays "The Third Man Theme" and Takadanobaba plays the Astro Boy theme²²⁸. Metropolis credits the 1989 jingles to Hiroaki Ide and says Minoru Mukaiya has composed around 170 since 2003¹¹¹. In February 2025, JR East announced it would phase out local platform melodies in favor of standard melodies played from the trains themselves²²⁸.

Other station sounds in Tokyo serve as guidance: bird-like sounds lead visually impaired riders to exits, and escalators announce their location¹¹¹.

In Boston

In Massachusetts, MassDOT committed, effective June 1, 2012, to install APS at all new traffic signals and, when possible, at existing signals during a major alteration or reconstruction; retrofits at MassDOT-maintained locations are considered on request²²⁹.

On the MBTA (more T sounds are in Trains and subways), the new Orange and Red Line cars came with a "door open chime" meant to help blind and low-vision riders find the doors, an idea the T's accessibility office compared to audible crossing signals. After complaints about loud, constant beeping, the T had 11 riders test five replacement sounds in late 2022; by March 2023 a less frequent chime was on 64 of 82 new Orange Line cars and all 12 new Red Line cars, the Boston Globe reported²³⁰.

Elsewhere in the world

• Japan: municipally chosen bird chirps and melodies at crossings, usually off after 8 p.m.; station departure melodies since 1988-89 on JR East²¹⁹²²⁸.
• Australia, New Zealand, Ireland, Singapore: the PB/5 locator chirp, "tick-tock" and "kapow"²²⁰.
• European Union: AVAS mandatory on all new electric and hybrid cars since July 1, 2021²²².
• China: GB/T 37153 follows UN R138 with minimums 2 dB higher²²⁴.
• Station jingles beyond Japan: Denmark's DSB, France's SNCF (a jingle by Michael Boumendil), Switzerland's vibraphone jingles and, since 2023, Singapore SMRT chimes based on local tunes²²⁸.

Report an error in this section