UN Regulation No. 28: Audible Warning Devices and Signals

Uniform Provisions Concerning the Approval of Audible Warning Devices and of Motor Vehicles with regard to their Audible Signals

Related groups: GRB and GRBP
UN R28 (1972)
31 Oct 1972 2011-01-06 09:59:00 UTC 00 series of amendments
UN R28 | Amendment 1 (1984)
21 Feb 1984 2011-01-06 10:02:29 UTC 1 00 series of amendments | Supplement 1
UN R28 | Amendment 2 (1992)
30 Oct 1992 2011-01-06 10:03:00 UTC 2 00 series of amendments | Supplement 2 00 series of amendments | Supplement 2 | Corrigendum 1
UN R28 | Amendment 3 (2001)
13 Jul 2001 2011-01-06 10:03:40 UTC 3 00 series of amendments | Supplement 3
UN R28 | Amendment 4 (2016)
5 Feb 2016 2016-02-10 10:24:14 UTC 4 00 series of amendments | Supplement 4 Based upon the adopted proposal: WP.29/2015/60

Proposal to allow vehicles to be run at idle during the test procedures and to change the minimum sound level requirement for vehicles of category M and N and motorcycles of a power greater than 7 kW from 93 dB to 87 dB.

UN R28 | Amendment 5 (2018)
7 Feb 2018 2018-05-04 08:41:06 UTC 5 00 series of amendments | Supplement 5 Based upon the adopted proposal: WP.29/2017/3

Proposal to update and clarify the regulation. The proposal refines definitions, removes the “AWD” abbeviation for “audible warning device” to avoid confusion with its more common use for “all wheel drive”, modifies some administrative communications, and proposes three-direction acoustic measurements. The proposal also aims to structure the regulation to enable its application to additional sound warning devices not presently regulated at the international level, excluding acoustic vehicle alerting systems (AVAS) which will be subject to a separate regulation on minimum vehicle sound levels.

Earlier texts may be available through the UN Official Document System.