SOURCE-LINKED REGULATION GUIDE
UN R51 — sound emissions from motor vehicles
Review the approval scope, measurement procedures and transitional provisions for sound emissions from category M and N vehicles in the published RegsUP edition.
Explore the scopeWhat does it cover?
UN R51 contains type approval provisions for sound emitted by motor vehicles with at least four wheels in categories M and N. It covers measurements intended to represent normal urban driving and additional sound emission provisions for relevant vehicles under a wider range of speeds and acceleration. Vehicle type, test conditions, conformity of production and transitional provisions appear in separate parts of the text.
Who is it for?
For vehicle manufacturers' homologation and acoustics teams, technical services carrying out sound tests and specialists assessing approval scope.
Which subjects are addressed?
- Scope and vehicle type definition for categories M and N
- Sound measurements representing urban driving
- Additional sound emission provisions and test annexes
- Approval, conformity of production and transitional provisions
Common question
Does R51 replace approval of tyre rolling sound?
No. R51 concerns vehicle type approval with regard to emitted sound. A tyre's own rolling sound and related tyre characteristics can fall under a separate regulation; assess the product and approval subject separately.
Published RegsUP edition
This page is tied to the published RegsUP working edition below; it is not an official consolidated text.
RegsUP record title: R51 — Uniform provisions concerning the approval of motor vehicles having at least four wheels with regard to their sound emissions
Working series: 03 · Included supplement: 10
RegsUP publication decision:
This is the RegsUP publication decision date, not the date the regulation entered into force.
RegsUP edition ID: b8aba98e-2393-4db0-b98a-b51a23f69243
Edition source digest (SHA-256): 03d1ee96c74fe388571d927c55c82591f0b1dcc08b014260e31fe84760afb54f
Source documents and references
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