Assisting the older driver - SWOV

Assisting the older driver
visual functions, need more contrast, a higher level of background luminance
and larger letter sizes than younger drivers to achieve the same level of
comprehension (Olson, Sivak & Egan, 1983). This can be accomplished by
raising the requirements for letter size and retro reflectivity of street‐name
signs.
Since older adult drivers need more time to act (turning into a street) after
having received directional information (e.g., a street name), the placement
of street‐name signs is probably also important: older adults should have
sufficient time to prepare and execute their actions. Both visibility and prior
notification can provide the driver with some extra time to act. This can
probably be accomplished by placing street‐name signs post‐mounted along
the side of the road and using advance street name signs to improve the
visibility of street name signs on major roads and grade‐separated junctions.
When different street‐names are used for different directions of travel on an
intersection, Staplin et al. (2001) recommend to separate the names on
intersection street name signs and to accompany them by directional arrows.
Lane‐use control signs
The decelerated perception‐reaction time of older adult drivers that is
responsible for the earlier mentioned extra time that older drivers need to
act, requires timely warnings of changes in lane configuration. Arrow
pavement markings that can provide this kind of information have the
disadvantage of being liable to wear, being less visible in bad weather
conditions and can be covered by cars at the intersection. Therefore, Staplin
et al. (1998) recommended to use overhead lane‐use control signs in advance
of the intersection as a supplement to pavement markings. Drivers should be
able to read these signs at least 5 seconds in advance of the intersection (at
operating speed; 50 m at 36 km/h), regardless of the specific lighting,
channelization or delineation treatments implemented at the intersection.
“One‐way” and “yield” signing
Other elements of the intersection the older adult driver should be informed
about as early as possible, are the obligatory direction of travel and right of
way. Research has shown that older adult drivers are overrepresented in
wrong‐way movements (see e.g., Blokpoel & De Niet, 2000; Crowley &
Seguin, 1986). This overrepresentation can be explained by the older drivers’
reduced peripheral vision and their decreased selective attention. To
compensate for these deficits, it appears to be important to give the most
relevant information a prominent place in the road environment. This can be
accomplished by more conspicuous signs, realized through provision of
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