In road safety management, an accident blackspot or black spot is a place where road traffic collisions have historically been concentrated. There may have been several reasons for this, such as a sharp drop or corner in a straight road, concealing oncoming traffic a hidden junction on a fast road, or poor or concealed warning signs at a crossroads.
History For some decades treatment of accident blackspots (e.g. by signage, speed restrictions, improving sightlines, straightening bends, or speed cameras) was a mainstay of road safety policy.
In 1973, Edward Douglas-Scott-Montagu, 3rd Baron Montagu of Beaulieu said in a debate in the House of Lords:
In July 1980, a SETRA report, named "Points noirs glissants" show that solutions which do not answer the diagnostic may be less efficient.Les aménagements de sécurité, Les routes principales interurbaines, mars 2006, SETRA
In 1990, in Australia, the Black Spot program was initially established under the Hawke government as a three-year initiative to run from 1990–91. The Government had plans to spend $110 million on improving safety at more than 1,000 sites, including intersections and bridges, over the three-year period to 30 June 1993. At the time, the program was administered by the Department of Transport and Communications.
On 12 September 2001, the European Commission published a White Paper titled 'European transport policy for 2010: time to decide' in which it expresses a need to carry out safety impact assessments and road safety audits, in order to identify and manage high accident concentration sections.https://eur-lex.europa.eu/eli/dir/2008/96/oj/eng
The 2008/96/EC directive defined the "ranking of high accident concentration sections" as "a method to identify, analyse and rank sections of the road network which have been in operation for more than three years and upon which a large number of fatal accidents in proportion to the traffic flow have occurred".Directive 2008/96/EC of the European Parliament and of the Council of 19 November 2008 on road infrastructure safety management This definition was removed in 2019 by the Directive (UE) 2019/1936 which amended Directive 2008/96/EC.Directive (UE) 2019/1936 du Parlement européen et du Conseil du 23 octobre 2019 modifiant la directive 2008/96/CE concernant la gestion de la sécurité des infrastructures routières
In 2023, to prioritize urban crash zones, the CEREMA provided a new open source method using Epanechnikov computations.https://www.cerema.fr/fr/actualites/priorisation-zones-accidentogenes-milieu-urbain-proposition
In 2024, 340 blackspots were identified in Morocco.https://fr.hespress.com/367580-accidents-routiers-frequents-340-points-noirs-identifies-sur-nos-routes.html
Switzerland In Switzerland since 2013, the owner of the road is required to take action on blackspots, based on a prescriptive text: the "VSS SNR 641724 Sécurité routière, gestion des points noirs".Points noirs sur les routes nationales 2020-2022
In 2011-2013, there were 1091 blackspots identified in Switzerland, including 767 in urban areas, 297 in rural areas and 27 on motorways. By 2020-2022, these numbers had reduced to 958, 684, 249 and 25.Points noirs sur les routes nationales 2022-2022, Office fédéral des routes OFROU, 20 décembre 2023
Works have been done on 88 blackspots.Points noirs sur les routes nationales 2022-2022, Office fédéral des routes OFROU, 20 décembre 2023
Criticism Current thinking has it that the benefits of these interventions are often overstated. Effects such as regression toward the mean,UCL and PA Consulting Group for Department for Transport UK national safety camera programme - Four-year evaluation report December 2005 Appendix H describes the effects of RTM risk compensation and accident migration combine to reduce the overall benefit.
In some cases it has been claimed that the end result of such interventions in accident blackspot areas is an increase in overall casualties. In one notable experiment, a number of accident blackspots were "treated" with a null treatment—placement of a garden gnome, according to some reports. Crash rates at these points were found to have decreased significantly in the following period, a finding which is taken as clear evidence supporting the theory of regression to the mean.
References
External links Discussion of accident blackspots