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EuroTest has now tested Europe's motorway road work zones for the third time, making this test a permanent part of the programme. The focus this time round was on 50 motorway road work zones in eleven European countries: Eight in Germany, seven in Austria, five in both Italy and Switzerland, four in France, the Netherlands and Spain, three in Croatia as well as two in both Denmark and Slovenia. And then there was the special situation in the UK where three road work zones were checked during the day and then again at night. The reason for this is that many road work zones on mainland Britain are changed completely at night, so that work can be intensified during low-traffic times. Due to this, it is not possible to compare the results of day and night measurements – extra testing at night was necessary. All of the sites tested were long-term road work zones on main European travel routes. The shortest road work zone was one kilometre long, the longest around 20 kilometres.

ADAC, which was in charge of the project, commissioned the Transport Infrastructure Institute ("Friedrich List" Faculty of Transport and Traffic Science) at Dresden University of Technology to perform the tests. The experts travelled along the road work zones in both directions, from 10 April to 2 June 2007, at least twice during the day and once at night, in a BMW 525d Touring fitted with state-of-the-art measuring systems. The measuring systems included a positioning system, comprising GPS, a reference station, inertial system and position measuring equipment, digital stereo cameras with their own computers for storing images which were used to measure distances and lane widths, an analogue scenery camera and a central measuring computer. The overall road work zone was generally measured during the day. There was, however, a single exception: The UK where measuring was also carried out at night due to altered traffic routing. Whilst driving along the road work zones, the position of signs and the location of lay-bys, for instance, were marked per touchscreen. The data was collected, documented per video both in digital and analogue form and subsequently analysed.

Safety potential
The "ARROWS" study (Advanced Research on Road Work Zone Safety Standards in Europe) by the European Commission, which is the only basic study in Europe to be performed on this topic, provided the methodological basis for our test. The result of the study was a practical handbook with recommendations for uniform European safety standards for road work zones. This handbook was used by ADAC and its partner clubs and traffic experts from science, planning and practice to develop a criteria catalogue for a comprehensive checklist. This list contains, for instance, the most important safety-related issues, in addition to matters concerning the layout and quality of a road work zone. When driving through the road work zone for the first time, the area was broken down into the following components: approach and work zone, reduction and tapering of lanes, entry and exit points, as well as the end of the road work zone. After each measurement, a digital questionnaire was completed on site.

Using the checklist, the following six theme blocks were checked:
Signs / road markings               Weighting: 25 percent

• Installation and correct position of all relevant signs, visibility, understandability, and condition of road signs ahead of the road work zone, along the road work zone and at the end of the road work zone
• Quality of road markings, self-explanatory

Driving safety                Weighting: 30 percent

• Width of traffic lanes
• Separation of bi-directional traffic
• Condition and cleanness of lanes

Traffic routing                Weighting: 20 percent

• Lane reductions
• Lane tapering, routing and exit taper
• Points of entry/exit within the road work zone

Requirements at night               Weighting: 10 percent

• Visibility of signs and road markings
• Protective equipment with reflectors
• Illumination and clear layout of the reduction and/or taper zone as well as the entry and exit points

Safety-relevant equipment              Weighting: 10 percent

• Installation of and distance between lay-bys with emergency phones
• Installation of emergency lanes along the entire length of the road work zone
• Safety zone before and separation of the work area
• Signs informing of speed traps

Information                  Weighting: 5 percent

• Information concerning the reason for, duration and total length provided at the beginning of the road work zone
• Repeated signs informing motorists of the remaining length of the road work zone
  The road work zones were rated on the basis of a points system with the following ratings: Very good, Good, Acceptable, Poor and Very poor.

Risk potential
In addition to the above, the risk potential of a road work zone was also considered. Lane reduction, tapering to the opposite lane, two-way traffic or points of entry and exit, for instance, are particularly relevant when it comes to the risk of an accident at a road work zone. Road work zones with a low risk received a bonus of up to ten percent and were hence able to compensate for their sometimes lower standard of safety measures.