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A FINNISH STUDY
Accidents
among pedestrians
The accident risk of urban pedestrians is at least 2-3 times higher in the dark than in daylight. Almost half of pedestrians injured on zebra crossings were again in dark or twilight. Road traffic victims rarely use a reflector When statistics were last compiled on reflector use amongst pedestrian victims in Finland, it found that none of the pedestrians killed in the dark was wearing a reflector. (This is in a country where reflector use is common ). Driving conditions in the dark Even at their best, car headlights create very little forward lighting. The range of dipped beam in particular is very short. A
pedestrian seen from say 50 metres presents a small visual image. The time
available to use one's senses is very short. Light clothing and the use
of effective reflectors improve visibility by
Visibility on an unlit road Visibility on an unlit road depends primarily on the degree of reflectivity of the person and background, the power and direction of the car headlights, the weather conditions and the eyesight of the driver. (Most drivers nowadays drive at speeds which make it difficult for them to see other road users in good time). A
driver using full beam will see a person on the road from as little as
200 metres away, (depending on their clothing) whilst a person wearing
a reflector will be seen from 700 metres (in same
The full beam of an oncoming car can cut a persons visibility down to 40-45 metres in ideal conditions. While a pedestrian wearing a reflector in same conditions is visible from 100-200 metres. For
pedestrians, the visibility problem is somewhat different. There may be
what seems to be sufficient light so they imagine the driver sees them
easily. In reality, they can merge into a dark
Visibility on a lit road Not all road illumination is well done, and where it isn't the pedestrian needs to wear a reflector. (Lighting causes a patchwork of shadows. Doorways, shop fronts, trees, walls, buildings as well as other traffic all contribute to the changing background. In this environment a pedestrian can apparently appear from nowhere. A reflector is a constant reminder to drivers that other road users are present). A driver's potential to see The
headlights of an oncoming car, scratches and dirt on the windscreen, distance
of the car in front, ageing eyesight (weakens night vision), headlights
directed to high up (oncoming traffic) or too low diminish drivers own
field of vision. As does dirty headlights. In a test driving on salted
roads
In poor weather conditions, a driver will spot a pedestrian from no closer than 15-20 metres. There's usually no time even to start breaking or give way (as most cars are driven too fast). The drivers potential to give way or stop No verge makes it likely that a pedestrian is in the car's path, which they always are when crossing the road. Reaction time to avoid collision is 1-2 seconds. For example a car travelling at 80 km/h proceeds 22 metres in one second and 44 metres in two. The later and more realistic distance of 44 metres is even in good conditions not enough to steer around someone if they are not wearing a reflector. (This takes no account of breaking, there wouldn't be time). In the same conditions a driver would need to have a further 35 metres breaking distance. (If traffic was coming from the other direction this luxury would not be available). This distance doubles on wet asphalt and quadruples on wet ice. Using reflectors to avoid accidents A retro-reflector refracts back light directed at it. (The brighter the car light the more effective the reflector). The
best place to attach a reflector is at the ends of the sleeves, at the
waist and close to the knee.
Removable reflectors attach to clothes with an easy-to-use mechanism that helps improve the pedestrians visibility from different directions. CENTRAL
ORGANISATION FOR TRAFFIC SAFETY IN FINLAND
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