Ursula Schrobitz, Klaus Krause, Werner Schnabel

• Um die Vor- und Nachteile des Rechtsabbiegens beim Farbzeichen "Rot" durch die Regelung "Grüner Pfeil" zu analysieren, wurden in den neuen Bundesländern folgende Untersuchungen durchgeführt: Unfalluntersuchungen, Konfliktbeobachtungen und Geschwindigkeitsmessungen, Simulationsuntersuchungen sowie Befragungen von örtlichen Dienststellen und Kraftfahrern. Die Ergebnisaussagen resultieren hauptsächlich aus den Konfliktbeobachtungen und den Befragungen, wobei folgende Ergebnisse hervorzuheben sind: - Eine wesentliche Sicherheitsbeeinträchtigung für Fußgänger und Fahrzeuge ist nicht nachweisbar. - Die Leistungsfähigkeit der beobachteten Knotenpunkte mit Grünpfeiltafel wird für Rechtsabbieger und darueber hinaus erhöht. Hierdurch werden mittlere Wartezeiten, die Zahl der Halte pro Kraftfahrzeug, der Kraftstoffverbrauch pro Kraftfahrzeug und der Rückstau verringert. - Baukosten in Knotenpunktbereichen werden reduziert. - Die Grünpfeilregelung ist nicht uneingeschränkt anwendbar. Es müssen zusätzliche Einsatzkriterien ausgearbeitet werden. Außerdem ist anzuzielen, Verkehrsteilnehmer zu regelgerechtem Verhalten zu erziehen sowie die optische und psychologische Wirkung des Grünpfeils zu verbessern.
• For the new federal states, a transitional regulation has been included into the German Highway Code (StVO) providing for the continued "Possibility of Right Turns on Red" as long as the stationary sign 23, Annex 1 to StVO-GDR, displaying a green arrow is attached to the Signal installation. By letter of 15-04-1991, the Federal Ministry of Transport commissioned an initial brief study of the green arrow regulation. Within the framework of that research, the following investigations had been carried out in the new federal states in order to study the advantages and drawbacks of the use of the green arrow sign as regards road safety and the capacity of signal-controlled junctions equipped in this manner: - accident investigations; - observations of traffic conflicts and speed measurements; - studies of event reconstructions; - interview surveys of local authorities and drivers. The information obtained mainly resulted from the observations of traffic conflicts and the interview studies. The following research findings should be pointed out: (1) No important detrimental effects of the green arrow sign regulation permitting right turns on red on the safety of pedestrians and cars could be established. (2) Improvement not only of the right turns capacity but also the overall capacity of the observed green-arrow-sign-equipped signal-controlled junctions. Specifically, the following can be achieved: - reduction of average delays - reduction of the stops per motor vehicle - fuel savings per motor vehicle - reduction of tailbacks. All this also results in improving the environmental situation by reducing traffic noise and emissions. (3) Reduction of junction construction costs. (4) The green arrow regulation cannot be applied unreservedly. In addition to the application conditions and recommendations included into the GDR Technical Standard (TGL 12096/04), further application criteria need to be defined. The following supplementary measures are desirable: - Educating road users to display the correct regulation behaviour - improving the optical and psychological effects of the green arrow. Further studies would be necessary if the final inclusion of the green arrow regulation into the StVO were to be considered. For this purpose a model test on this problem, to be undertaken in the old federal states, is being proposed by the Federal Highway Research Institute (BASt).