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ECE R-138
Quiet Road Transport Vehicles (QRTV)
Applies to
M, N
Topic
Emissions & sound
Framework
UN ECE
Velocert services
European
Overview
UN Regulation No 138 lays down uniform provisions for the approval of Quiet Road Transport Vehicles (QRTV) with regard to their reduced audibility. Its annexes cover methods and instruments for measuring the sound made by motor vehicles.
Current series: 02 series, Supplement 1 (in force 26 September 2025); this summary is based on the version published on EUR-Lex, the original version (2016). GlobalAutoRegs also lists Supplements 2 and 3 to the 02 series with no entry-into-force date. Checked on GlobalAutoRegs, 1 November 2026. For the current text, see the UN (UNECE) page.
Scope
It applies to electrified vehicles of categories M and N that can travel in normal mode, in reverse or in at least one forward gear without an internal combustion engine operating, with regard to their audibility.
The regulation applies to the following vehicle categories:
M
Passenger vehicles
N
Goods vehicles
Official source
For the requirements of this regulation, refer to the official text in force and its amendments.
Official UNECE text