Methodology for assessing the lighting of pedestrian crossings based on light intensity parameters

One of the possible preventive measures that could improve safety at crossings is to assess the state of illumination of the lighting installation located in the transition area for pedestrians. The City of Warsaw has undertaken to comprehensively assess the pedestrian crossings to determine the level of road safety and the condition of lighting. The lighting conditions related to pedestrian crossings without traffic lights in three central districts of the city were investigated. The conducted field research and the work of the team of experts lead to the development of tools to assess the level of risk due to the lighting conditions measured at night. The newly developed and used method of assessment and the experience gained should provide a valuable contribution to the development of uniform risk assessment rules for pedestrian crossings in Poland. The authors of this paper have attempted to systematize the description of the method of evaluation of the lighting installed in the area of pedestrian crossings.


Introduction
As is apparent from the reports on road safety [1,2] in Poland for many years, there is large number of accidents at pedestrian crossings (Fig. 1).

Fig. 1.
The number of road accidents on pedestrian crossings in Poland year 2000-2015 [1].

GAMBIT 2016
Action was taken to improve the safety of vulnerable road users in cities [3].Despite the endeavour to improve the safety of pedestrians in Warsaw in 2011 -2015, there was no clear trend of any reduction in the number of accidents with pedestrians (434 -490 accidents / year).Only in 2015 was there a decrease down to 390 accidents.Due to their low statistical numbers, accidents with pedestrians were no longer a map of "black points."To act preventively, a map of the level of hazard for pedestrian crossings should be created, regardless of whether there had been an accident involving pedestrians or not.Acting with the aid of a map of dangers, the road manager can be proactive, not waiting for accidents and fatalities to take place.
The lighting of pedestrian crossings is one of the elements of road safety control [3].In order to improve the current state of hazards to vulnerable road users a comprehensive inspection of pedestrian crossings must be carried out [4,5].Recommend the pedestrian crossings to modernize in line with a full assessment of the other road safety factors.On this basis the risk factors should be identified and classified.As a result, it will be possible to mark the pedestrian crossings which require corrective action as regards lighting infrastructure.
It should be noted that uniform and comprehensive safety control procedures, dedicated to pedestrian crossings with a focus on parameterized factors of lighting, have not been developed and implemented in Poland so far.The authors of this publication have made efforts to systematize the process of evaluating the existing lighting of pedestrian crossings for the purposes of the upgrades carried out in Warsaw.It should be noted that the measures taken to evaluate the state of illumination were carried out in parallel with the work of the Road Safety Movement team of auditors, whose task was to assess the other elements affecting the safety of pedestrians.
One of the elements to be evaluated was the lighting of the pedestrian crossings.In urban agglomerations, the assessment of the lighting infrastructure is very important from the point of view of maintaining or improving lighting conditions.The City of Warsaw has undertaken to comprehensively evaluate the existing pedestrian crossings to determine the level of road safety and assess the lighting.Research on pedestrian crossings without traffic lights was carried out in the three central districts of the city.It should be emphasized that no similar project had been carried out in Poland before.The research literature [4][5][6] preceding the conceptual and field work does not indicate any useful methodologies for the evaluation of lighting parameters.The authors of the literature on the subject encountered just one case [4] where an attempt was made to reach an objective numerical pedestrian risk assessment, giving weight points and weighing the individual parameters of pedestrian crossings.However, in this method the assessment of lighting does not contain the essential quality parameters.Research literature [4,5] indicates that the factor of assessing lighting in the proposed evaluation procedures was treated ambiguously and did not define the lighting parameters and values, or the recommended limits.Balance and weight points cannot be transferred directly from Italian to Polish conditions due to the specificity of the local behaviour of managers and pedestrians and different traffic regulations.Therefore, it had to develop an entirely new, comprehensive evaluation method that allows for the identification of the risk factors for the evaluation of pedestrian crossings.One of them was the state of the lighting of pedestrian crossings.The authors of the Polish methods of assessment decided to split the final evaluation into the lighting parameters and other parameters of road safety (because of the difficulty in determining the gravity of the share of the particular criteria influencing the outcome of the final comprehensive assessment of road safety at pedestrian crossings).Therefore, this article discusses only the assessment of the state of illumination.

Assessment of the state of lighting in the area of pedestrian crossings
The lighting of pedestrian crossings in urban areas is often implemented by means of a street lighting installation or using special dedicated luminaires.The lights installed at a pedestrian crossing should also ensure that where: -OE is objective evaluation, -RC is evaluation associated with lighting the horizontal plane, -REVD1 is evaluation associated with lighting the vertical plane in direction 1, -REVD2 is evaluation associated with lighting the vertical plane in direction 2, -f1, f2, f3, are the weight factor = 0,33.The final evaluation of the state of lighting pedestrian crossings FR is delivered on the basis of the partial assessment of the subjective and the objective: where: -FR is final ranking, -SE is subjective evaluation, -OE is objective evaluation, -f4, f5, are the weight factor = 0,5.
In the case of incorrect levels of illumination or improper lighting conditions, technical solutions were proposed to improve the view of pedestrians at night both on the crossing itself and in the waiting area (recommendations included a range of solutions ranging from the cheapest and easiest applications to comprehensive improvements in the lighting system).As a result of the work of established data mart lighting parameters.Pedestrian crossings can be filtered through various criteria, e.g.ratings.Part of the work identified a number of irregularities, e.g.41 of the examined cases where maintenance procedures on the street lighting should be immediately undertaken.

Summary
As a result of our activities, using the research literature and the expertise on the subject, a measuring procedure was developed to unambiguously classify the lighting performance on a test of Warsaw pedestrian crossings.The material prepared this way makes it possible to carry out preventive management measures and investment.
In spite of the existing standards and guidelines, the lighting conditions at pedestrian crossings in Poland are not consistently regulated.There is no clear and verifiable research to define the need for the installation of street lighting and/or additional dedicated lighting.Furthermore there is no legislation defining the lighting conditions that should be met at pedestrian crossings.The technical specifications of tenders for the upgrading of street lighting on pedestrian crossings does not directly define any precise design requirements for contractors.Another problem are the shortcomings at the investment stage and concerning the use of the research verifying the actual state of the lighting on pedestrian crossings.In the

Fig. 2 .ForTab. 2 . 4 DOI
Fig. 2. The basic geometry of pedestrian crossings with the indication of the measurement points.