Страница 3: ДСТУ CEN/TR 13201-1:2016. Road lighting — Part 1: Guidelines on selection of fighting classes (62747)

The values stated in the column are an example. Any adaptation of the method or more appropriate weighting values can be used instead, on the national level.

A.2 Example for lighting class P

Time dependent change of use intensity and ambient luminance, two time intervals (At1, and At2) considered; e.g. from switch on time until midnight and from begin of morning rush hour until switch off time (△t1), and from midnight until begin of morning rush hour (At2).

Table A.2 — Time dependent selection of parameters - lighting class P

For the determination of the lighting class P to be applied the weighting values for the different parameters have to be added for each of the time intervals considered. The maximum value of the sum of the weighting values (here VWS, max = 2) is used to calculate the number of the normal lighting class P as 6 - VWS = 4 to be applied (P4). The minimum value of the sum of the weighting values (here VWS, min = 0) leads to the adaptive lighting class P6 which could be applied in terms of the illuminance level in the time interval At2.

Annex В
(informative)

Alternative method for selection of lighting classes

This method is based on a functional or administrative road classification defined by highway authorities and provides a more refined solution within each lighting class. The road designations are the main entries in the first column of a table. In the table, the consecutive columns allow selecting progressively the weight of five different coefficients attached to the different parameters mentioned in the header of the table.

These parameters are:

1. road type and speed limit;

2. traffic composition;

3. traffic volume;

4. ambient light;

5. mental task load.

The overall weighted coefficient results from the product of the five coefficients attached to these parameters. It should be noted that the first three parameters are dependent and always have an influence on the overall coefficient. At the same time the last two parameters either may have an influence or not on the overall coefficient for the reason they are independent. In “normal” situations they have no influence and the value of their coefficient is 1, conversely when their influence is high a coefficient of 1,25 has been retained. Furthermore, a consideration is given for these last two parameters whether the occurrence of the situation is currently possible (•) or unlikely ( — ). Depending on the resulting combinations, the overall coefficient can be found in one of the three columns titled: Line I, Line II and Line III. When a value is present in one of these three columns, it is the overall coefficient retained for the given situation.

The last step in the classification process is then to use this overall coefficient as the entry in the diagram of the figure attached to the table. In this diagram, three straight lines are drawn in a system of coordinates and are respectively named Line I, Line II and Line III with reference to the corresponding columns of the table. In abscissa of this diagram we can read the overall coefficient. In ordinate we can read average maintained luminances or illuminances. Parting from the overall coefficient of a given situation in abscissa, the level of luminance or illuminance is reached in ordinate on the corresponding straight Line I, II or III to give, at the same time, the range of classification spread along the scale of ordinates.

Two tables and two figures have been created:

• Table B.1 and Figure B.1 for M and C classes;

• Table B.2 and Figure B.2 for P classes.

In Figure B.1, the scale in ordinate has been primarily established for M classes in luminance. The correspondence in illuminance for C classes is based on 3 values of the Q0 factor of the road surface.

Table B.1 incorporates the considered principles and values. At national level further developed code of practice for road lighting is recommended based on the administrative or functional classification of roads. Road descriptors given in Column 1 of Table B.1 should be retained or amended.

For the determination of the lighting class M or C to be applied to a given situation, the appropriate coefficients are selected in the different lines of the table of a given road descriptor. Once the overall coefficient is determined in one of the three columns Line I, Line II or Line III, the results can be transferred on to Figure B.1.Two situations for the class search have been highlighted in two examples at the end of this annex using Table B.1 and Figure B.1.Table B.1 — Selection of the M or C lighting class from the road or street characteristics