Visual Performance, Comfort and Pleasantness for Pedestrians, Cyclists and Residents - Road Lighting: Fundamentals, Technology and Application - page 63

Zones of proximity

public zone

m 0 0.5 1.2 4 10

Fig. 5.4 Zones of proximity according to the nature of the social contact

more applicable to different skin colours. For a recognition distance of 4 m these
studies show that facial luminances of 0.1 cd/m 2 (TI

= 0) (Fotios and Yang 2013 )to

0.18 cd/m 2

15 %) (Kohko et al. 2008 ) are required. For a face reflectance of
0.4 this corresponds to 0.8 lx and 1.5 lx semi-cylindrical illuminance, respectively.
Most of the studies described here involved continuous observation of the target
person during the approach. In reality, a person will not look at another person
continuously while approaching that person in the street. Fotios et al. ( 2014a , b )
investigated at what distance and for how long do test persons fixate their direction
of view on other pedestrians in the street. For this purpose the test persons were
equipped with an eye-tracker. On the basis of the results of their study, the authors
propose that 15 m as the distance and 0.5 s as the observation time should be employed
when investigating the effects of lighting on interpersonal judgments.

(TI =

5.1.3 Visual Orientation and Guidance

Visual orientation in complete darkness is impossible. Without light, we do not know
where we are or which way to go. Orientation is a complex process involving param-
eters such as expectation, experience and visual memory. A resident familiar with
his environment needs less lighting for orientation purposes than do those less fa-
miliar with the environment in question. Good visual orientation implies the ability
to identify houses and other buildings and features of the environment, including
road junctions. The eye-tracker investigation mentioned earlier showed that the test
persons walking along a route looked at houses, roads (not the pavement on which
they walk) and trees for slightly more than 50 % of the time (Davoudian and Rayn-
ham 2012 ). Street signs and house numbers should, of course, be legible as well.