Contents The agreement itself is brief and simple, and its most important article is article 2. This article states that with the exception of certain exceptionally dangerous materials, hazardous materials may in general be transported internationally in wheeled vehicles, provided that two sets of conditions be met:
Annex A regulates the merchandise involved, notably their packaging and labels. Annex B regulates the construction, equipment, and use of vehicles for the transport of hazardous materials. The appendices consist of nine chapters, with the following contents
General provisions: terminology, general requirements Classification: classification of dangerous goods (CDG) Dangerous Goods List sorted by UN number, with references to specific requirements set in chapters 3 to 9; special provisions and exemptions related to dangerous goods packed in limited quantities Packaging and tank provisions Consignment procedures, labeling, and marking of containers and vehicles. Construction and testing of packagings, intermediate bulk containers (IBCs), large packagings, and tanks Conditions of carriage, loading, unloading, and handling Vehicle crews, equipment, operation, and documentation Construction and approval of vehicles
Hazard classes The classes of dangerous goods according to ADR are the following:
Class 1 Explosive substances and articles Class 2 Gases, including compressed, liquified, and dissolved under pressure gases and vapors Flammable gases (e.g. butane, propane, acetylene) Non-flammable and non-toxic, likely to cause asphyxiation (e.g. nitrogen, CO2) or oxidisers (e.g. oxygen) Toxic (e.g. chlorine, phosgene) Class 3 Flammable liquids Class 4.1 Flammable solids, self-reactive substances, and solid desensitized explosives Class 4.2 Substances liable to spontaneous combustion Class 4.3 Substances which, in contact with water, emit flammable gases Class 5.1 Oxidizing substances Class 5.2 Organic peroxides Class 6.1 Toxic substances Class 6.2 Infectious substances Class 7 Radioactive material Class 8 Corrosive substances Class 9 Miscellaneous dangerous substances and articles Each entry in the different classes has been assigned a 4 digit UN number. It is not usually possible to deduce the hazard class of a substance from its UN number: they have to be looked up in a table. An exception to this are Class 1 substances whose UN number will always begin with a 0. See List of UN numbers.
Tunnel classifications The ADR Secretariat has defined a classification system for major tunnels in Europe. "The categorization is based on the assumption that in tunnels there are three major dangers that may cause numerous victims or serious damage to the tunnel structure." It is the responsibility of each national authority to categorize its tunnels accordingly. The classes ranges from A (least restrictive), to E (most restrictive). As of 2010, in the United Kingdom for example, the least restrictive was the tunnel carrying the A299 to the Port of Ramsgate, while the most restrictive were several tunnels in East London, including the Limehouse Link tunnel, the Rotherhithe Tunnel, the Blackwall Tunnel and the East India Dock Link Tunnel.
ADR pictograms ADR pictograms for chemical hazards are based on GHS Transport pictograms and Non-GHS transport pictograms
See also Dangerous goods European hazard symbols Hazchem – a system used in the United Kingdom, Australia, and New Zealand for marking dangerous goods ATEX directive – two EU directives governing permitted equipment in explosive environments
References Notes
ADR 2023 https://unece.org/info/Transport/Dangerous-Goods/pub/373077 Sources
2 on the United Nations Economic Commission for Europe website
External links
3 UN Model regulations ("Orange book") 2019 How to assign a UN Number and proper shipping name ADR Book - Dangerous Goods by Road