World Forum for Harmonization of Vehicle Regulations

The World Forum for Harmonization of Vehicle Regulations is a working party of the Sustainable Transport Division of the United Nations Economic Commission for Europe. Its responsibility is to manage the multilateral Agreements signed in 1958, 1997 and 1998 concerning the technical prescriptions for the construction, approval of wheeled vehicles as well as their Periodic Technical Inspection and, to operate within the framework of these three Agreements to develop and amend UN Regulations, UN Global Technical Regulations and UN Rules.
WP.29 was established in June 1952 as the "Working Party of experts on technical requirement of vehicles", while its current name was adopted in 2000.
At its inception, WP.29 had a broader european scope. Since 2000, the global scope of this forum was recognized given the active participation of Countries in all continents.
The forum works on regulations covering vehicle safety, environmental protection, energy efficiency and theft-resistance.
This work affects de facto vehicle design and facilitates international trade.

1958 Agreement

The core of the Forum's work is based around the "1958 Agreement", formally titled "Agreement concerning the adoption of uniform technical prescriptions for wheeled vehicles, equipment and parts which can be fitted and/or be used on wheeled vehicles and the conditions for reciprocal recognition of approvals granted on the basis of these prescriptions". This forms a legal framework wherein participating countries agree on a common set of technical prescriptions and protocols for type approval of vehicles and components. These were formerly called "UNECE Regulations" or, less formally, "ECE Regulations" in reference to the Economic Commission for Europe. However, since many non-European countries are now contracting parties to the 1958 Agreement, the regulations are officially entitled "UN Regulations". According to the mutual recognition principle set in the Agreement, each Contracting Party's Type Approvals are recognised by all other Contracting Parties.

Participating countries

The first signatories to the 1958 Agreement include Italy, Netherlands, Germany, France, Hungary, Sweden and Belgium. Originally, the agreement allowed participation of ECE member countries only, but in 1995 the agreement was revised to allow non-ECE members to participate. Current participants include European Union and its member countries, as well non-EU UNECE members such as Norway, Russia, Ukraine, Croatia, Serbia, Belarus, Kazakhstan, Turkey, Azerbaijan and Tunisia, and even remote territories such as South Africa, Australia, New Zealand, Japan, South Korea, Thailand and Malaysia.
, the participants to the 1958 Agreement, with their UN country code, were:.
Most countries, even if not formally participating in the 1958 agreement, recognise the UN Regulations and either mirror the UN Regulations' content in their own national requirements, or permit the import, registration, and use of UN type-approved vehicles, or both. The United States and Canada are the two significant exceptions; the UN Regulations are generally not recognised and UN-compliant vehicles and equipment are not authorised for import, sale, or use in the two regions, unless they are tested to be compliant with the region's car safety laws, or for limited non driving use.

Type approval

The 1958 Agreement operates on the principles of type approval and reciprocal recognition. Any country that accedes to the 1958 Agreement has authority to test and approve any manufacturer's design of a regulated product, regardless of the country in which that component was produced. Each individual design from each individual manufacturer is counted as one individual type. Once any acceding country grants a type approval, every other acceding country is obliged to honor that type approval and regard that vehicle or item of motor vehicle equipment as legal for import, sale and use.
Items type-approved according to a UN Regulation are marked with an E and a number, within a circle. The number indicates which country approved the item, and other surrounding letters and digits indicate the precise version of the regulation met and the type approval number, respectively.
Although all countries' type approvals are legally equivalent, there are real and perceived differences in the rigour with which the regulations and protocols are applied by different national type approval authorities. Some countries have their own national standards for granting type approvals, which may be more stringent than called for by the UN regulations themselves. Within the auto parts industry, a German type approval, for example, is regarded as a measure of insurance against suspicion of poor quality or an undeserved type approval.

UN Regulations

, there are 135 UN Regulations appended to the 1958 Agreement; most regulations cover a single vehicle component or technology. A partial list of current regulations applying to passenger cars follows

General lighting

Automated/autonomous vehicle regulations

North America

The most notable non-signatory to the 1958 Agreement is the United States, which has its own Federal Motor Vehicle Safety Standards and does not recognise UN type approvals. However, both the United States and Canada are parties to the 1998 Agreement. UN-specification vehicles and components which do not also comply with the US regulations therefore cannot be imported to the US without extensive modifications. Canada has its own Canada Motor Vehicle Safety Standards, broadly similar to the US FMVSS, but Canada does also accept UN-compliant headlamps and bumpers. The impending Comprehensive Economic and Trade Agreement between Canada and the European Union could see Canada recognise more UN Regulations as acceptable alternatives to the Canadian regulations. Canada currently applies 14 of the 17 ECE main standards as allowable alternatives - the exceptions at this point relate to motorcycle controls and displays, motorcycle mirrors, and electronic stability control for passenger cars. These three remaining groups will be allowed in Canada by the time the ratification of the trade deal occurs.


Rather than a UN-style system of type approvals, the US and Canadian auto safety regulations operate on the principle of self-certification, wherein the manufacturer or importer of a vehicle or item of motor vehicle equipment certifies—i.e., asserts and promises—that the vehicle or equipment complies with all applicable federal or Canada Motor Vehicle Safety, bumper and antitheft standards. No prior verification is required by a governmental agency or authorised testing entity before the vehicle or equipment can be imported, sold, or used. If reason develops to believe the certification was
false or improper — i.e., that the vehicle or equipment does not in fact comply — then authorities may conduct tests and, if a noncompliance is found, order a recall and/or other corrective and/or punitive measures. Vehicle and equipment makers are permitted to appeal such penalties, but this is a difficult direction. Non-compliances found that are arguably without effect to highway safety may be petitioned to skip recall requirements for vehicles already produced.

Regulatory differences

Historically, one of the most conspicuous differences between UN and US regulations was the design and performance of headlamps. The Citroën DS shown here illustrates the large differences in headlamps during the 1940-1983 era when US regulations required sealed beam headlamps, which were prohibited in many European countries. A similar approach was evident with the US mandatory side marker lights.
It is not currently possible to produce a single car design that fully meets both UN and US requirements, but it is growing easier as technology, and both sets of regulations, evolve. Given the size of the US vehicle market, and differing marketing strategies in North America as opposed to the rest of the world, many manufacturers produce vehicles in four versions: North American, UNECE right-hand drive, UNECE left-hand-drive, and Rest of the World (for non-regulated countries or countries with poor market fuel quality.

1998 Agreement

The "Agreement concerning the Establishing of Global Technical Regulations for Wheeled Vehicles, Equipment and Parts which can be fitted and/or be used on Wheeled Vehicles", or 1998 Agreement, is a subsequent agreement. Following its mission to harmonize vehicle regulations, the UNECE solved the main issues preventing non-signatory Countries to the 1958 Agreement to fully participate to its activities.
The 1998 Agreement is born to produce meta regulations called Global Technical Regulations without administrative procedures for type approval and so, without the principle of mutual recognition of Type Approvals. The 1998 Agreement stipulates that Contracting Parties will establish, by consensus vote, United Nations Global Technical Regulations in a UN Global Registry. The UN GTRs contain globally harmonized performance requirements and test procedures. Each UN GTR contains extensive notes on its development. The text includes a record of the technical rationale, the research sources used, cost and benefit considerations, and references to data consulted. The Contracting Parties use their nationally established rulemaking processes when transposing UN GTRs into their national legislation. The 1998 Agreement currently has 33 Contracting Parties and 14 UN GTRs that have been established into the UN Global Registry. Manufacturers and suppliers cannot use directly the UN GTRs as these are intended to serve the Countries and require transposition in national or regional law.

2013 Transatlantic Trade and Investment Partnership (proposed)

As part of the Transatlantic Trade and Investment Partnership negotiations, the issues of divergent standards in automobile regulatory structure are being investigated. TTIP negotiators are seeking to identify ways to narrow the regulatory differences, potentially reducing costs and spurring additional trade in vehicles.


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