The purpose of this annex is to provide guidance on the classification of a road network into operating environments on the basis of three criteria:
This chapter describes the attributes used for classification of Operating Environments.
One of the key elements in an Operating Environment is the physical layout of the road section itself. The road user is naturally well aware of the road, which he/she is using, and will base his/her expectancies on the ITS as well as other services on the road type. There are two basic types of roads with regard to the Operating Environments:
Only lanes for motor vehicles (including dedicated bus lanes) are included in the counting of lanes. If there are more than two lanes in at least one of the driving directions, but it is not a case of being a motorway, the road should be classified among other roads than motorways. Hard shoulders should not be counted as lanes, even if used as temporary driving lanes.
In addition to the road types described above, the TEN-T (Trans-European Network – Transport) has some physically distinct sections, which set special requirements to road services including ITS. Such sections are:
The road section concerned may also have a need for special service levels related to its role in the transport network. The roles important for the ITS service provision include:
This typology is a basis for defining Operating Environments and assigning a letter code to each type. Traffic flows and safety (see next points) will provide further details (distinguished with numbers).
Note: that any section of the road/motorway can only belong to one typology. This is to ensure the summing up of the network lengths based on the Operating Environments.
Note that both for traffic flow impact and safety concerns, the road section is treated as a whole, consisting of both driving directions, even though in some cases the conditions might vary from one direction to the other. Again, this is done to ensure correct summing up of network lengths. If, however, a road operator insists on treating the directions as separate, this is allowed as long as this treatment is carried out consistently in the whole network of the country in question and specifically reported.
The existence of traffic flow impact is related to the actual flow situation on the specific road section in terms of traffic volumes.
It is quite obvious that ITS service levels need to be linked to the volume of traffic and how it varies with time. We aim at specific quantitative thresholds for annual average daily traffic (AADT) to set up the categories for traffic flow impact. This is described accordingly:
Note that the thresholds above leave room for member states and road operators to use their own thresholds set according to national or road operator’s own criteria. Naturally, local circumstances can also motivate deviation from the general principles and thresholds for specific road segments.
The existence of potential road safety concerns is related to the actual situation on the specific road section.
Two safety categories are to be used:
There are three methods used to identify a section with potential safety concerns:
The first method is recommended as the one most closely related to the safety experienced by the driver. Naturally, local circumstances can motivate deviation from the afore-mentioned methods and thresholds for specific road segments.
The actual Operating Environments are determined on the basis of the attributes listed above. In addition to these, the road operators may also voluntarily choose to use additional criteria for classifying their road network. Such additional attributes are most likely related to weather, environmental and heavy goods transport concerns. These attributes are elaborated upon below.
No agreement on the method for classification of these other attributes has been reached so far.
The road/motorway is classified as having critical weather-related problems, if severe weather problems related to snow, ice, fog, heavy rainfall and/or strong cross-winds considerably and frequently affect traffic – especially in the wintertime.
The road/motorway section has critical environment concerns if it is passing through an area sensitive to environmental (pollution, noise) impact or affected by regulations such as groundwater areas, parks, residential areas, schools, playgrounds, etc.
The link, corridor or network is of particular importance for freight transport. The proportion of heavy goods vehicles of all traffic or the average daily number of heavy goods vehicles are regarded as high by the road operator or the road/motorway is leading to a major logistics hub such as a port, airport (cargo), freight village etc.
This section describes how the road operators should classify their road networks into Operating Environments. The definition of what constitutes the network to be classified is decided by the road operator in question.
Note that if the road operator cannot classify a specific road section into any of the Operating
Environment categories given in the document, the partner should choose the Operating Environment best fitting the specific road section, and to inform the authors of this document of the characteristics of all such sections poorly fitting into the current Operating Environments. Such cases will be considered when future versions of the Operating Environments are being proposed and when this classification guidance is being updated. It should be noted that the ultimate goal is to achieve a consistent European methodology for classifying the road network into Operating Environments.
The classification method proposed takes into account the possibility of a later integration of the Operating Environment classification with a map-tool, allowing for network classification to be displayed in a map.
In practice, it seems to be easier to classify road networks into Operating Environments criteria by criteria, as often each criterion is best dealt with by a specific expert. A congestion expert can easily classify the network by traffic flow impact, whereas another expert on safety will quickly classify the whole network according to the existence of potential safety concerns.
The whole relevant road network is to be classified. For the classification, the network is to be divided into sections according to the basic factors determining the Operating Environment – physical layout, network typology, traffic flow impact and potential safety concerns as well as the additional attributes (weather, environment, freight), which the road operator chooses to use. This means that a new section could start each time, when the category of at least one of these factors and attributes changes. This may result in road sections of very varying length (from hundreds of metres to hundreds of kilometres). The road operators may also cut the sections also at other points, according to their own uses and preferences. The general recommendation is to use motorway exits and major road junctions as the points of division for the road network, because this will simplify some later procedures such as map-matching. Hence, a road section normally runs from one exit/ junction to another, but not necessarily the next one.
Naturally, road characteristics, traffic flow and road safety conditions evolve over time partly due to ITS deployments. Hence, the need to update the Operating Environment classification should be assessed at regular intervals.
An efficient way of carrying out the classification is to use an Excel tool for this. The road network is filled in into the Excel workbook road by road and motorway by motorway, section by section. All network elements classified should include official names (junction names, road names and/or TMC location codes if available) since this simplifies the matching of elements for various applications and supports error detection and quality management in general. The worksheet has the following columns:
The other columns of the worksheet can be used for describing the coverage (%) of the road/ motorway section with different core ITS services of specific service levels, or e.g. the values of the deployment indicators during a year or a project phase. The excel sheet can also be used as direct input to a map or other ways of reporting the classification.
The empty Excel worksheet for the classification is presented in Figure C-1. An example of a filled excel sheet is given in Figure C-2.
There are two main ways to report the classification in addition to the use of the Excel document as the final outcome. The target should be to connect the report directly to the classification of the Operating Environments either in the Excel tool so that the reports are more or less automatically generated after the data from the road network has been properly filled in.
The first way of reporting is to use a map and geographic information system (GIS). The choice of the mapping software should comply with the mapping requirements of the overall deployment monitoring and reporting requirements related to the ongoing situation of the road operator.
The second way is to report the lengths of each Operating Environment, and this can be carried out on the basis of the Excel worksheet. This is useful for the deployment target setting and deployment monitoring purposes. An example is given in Table C-1 below.
Figure C-1: A screenshot of the excel worksheet for classification of road network into Operating Environments.
It is also essential that the road operator describes in detail how they have made the classification into Operating Environments, if their own method of classification differs from the one proposed in these guidelines. This is crucial as the ultimate goal is to arrive at a common and consistent classification in Europe. In order to reach a consensus, it is essential that all involved understand the routines and cultures applied by each partner and their reasons for such ways of applications.
If the classification is reported with another map tool, the same colours should be used in the map tools utilised. These colours are the standard HTML colours indicated in Figure C-2.
Table C-2: The colour scheme to be used for the Operating Environments in the maps
