Bright Sun, Deadly Collisions
by Marianne Costantinou, San Francisco Examiner, Oct. 12, 1998
re-printed from the "San Francisco Examiner" October 12, 1998
Driving off into the sunset might be romantic in the movies, but on city streets and highways, the glare from the setting sun can be deadly.
Sun glare was blamed for at least two pedestrian fatalities in San Francisco in past weeks, one as recently as Oct. 2, when Caroline Drewes, 80, a beloved former Examiner reporter and one of the first female journalists in San Francisco to cover non-society news, was hit by a car as she was walking with her dog across Jackson Street in Pacific Heights.
The driver never saw her in the crosswalk, he told police. The setting sun was directly in his eyes as he crested the hill at Lyon Street about 6:30 p.m.
Although glare can be dangerous year-round, whether in urban areas or remote deserts, it is an especially big problem in San Francisco at this time of year and in early spring, when several factors conspire against pedestrians and drivers during the worst traffic hours of the day: rush hour.
Nationwide, glare is the official cause of only a fraction of fatal crashes across the country - 195 in 56,793 - according to the National Highway Traffic Safety Administration of the U.S. Department of Transportation.
But the statistics belie the danger. Some police departments - such as San Francisco's - don't keep statistics about the causes of accidents. And even those that do - including the Highway Patrol - don't list glare as a category for investigating officers to check off. In California, highway accidents caused by a driver blinded by sun glare may be hidden in a category like "driving in speeds in excess of safety," CHP spokesman Steve Kohler said.
Because statistics are not kept in San Francisco, it is not known how many accidents can be blamed on glare. Officer Ray Shine, of the motorcycle unit of the San Francisco Traffic Police Division, handled the cases of Drewes and another pedestrian, Karen Kennedy, 38, who was crossing the road at the Lincoln Golf Course at El Camino del Mar near Land's End about 5:30 p.m. Aug. 20 when she was hit and killed by a westbound driver blinded by the sunlight.
To Shine, who has spent 18 years on the road monitoring traffic, glare is even more dangerous than the much more publicized peril of driving in fog.
"I think most people slow down in fog," he said. "But in glare they continue, because it's a nice clear day."
Drivers are blinded by the sunlight as it hits their windshield. But there is also "veiled glare," which is indirect sunlight that comes in at an angle, or reflects off glass towers and other cars. Like a veil, you can see through it, but not very clearly.
A dirty windshield only worsens the problem, according to "Responsible Driving," a driver's ed textbook published by the Automobile Association of America.
Illuminated by the sunlight, every dust particle, every streak, every smudge becomes magnified, so the only thing that can be seen is the windshield dirt instead of the road. Meanwhile, though the windshield is bright, the low-slung sun of sunrise and sunset is casting long shadows in the road ahead, making seeing even harder.
But glare is not only a problem when motorists are driving into the sun, Shine said. He blames a lot of red light running on glare, too.
When the sun is behind motorists, he said, the light often bounces off the reflectors of the traffic lights ahead, causing them to have the same brightness - and to look like they are all the same color. Some motorists run the red light because it looks the same upon approach as the green light they saw moments before.
Glare is especially acute this time of year and in early spring, which astronomers call the equinox. Several factors only worsen the problem for rush-hour commuters in San Francisco.
*Glare is at its worst when the sun is low, toward the horizon. That typically is the hour or so after sunrise and before sunset, said Bing Quock, assistant chairman of the Morrison Planetarium at the California Academy of Sciences. At this time of year, that means glare is a problem from about 7:30 a.m. to 9 a.m., and from 5 p.m. to 6:30 p.m. - the height of rush-hour traffic.
*The sun rises and sets exactly due east and west in the weeks before and after the official start of spring on March 20 and autumn on Sept. 21.
*San Francisco, like many cities, is largely laid out in a grid pattern, with streets running north to south (like Van Ness Avenue), and east to west (like Geary). Most office and retail jobs are downtown, which means that morning commuters tend to head east - which means they have to drive into the sun to get to work. Many residential neighborhoods are on the west side of town, which means that commuters heading home are once again driving toward the sun.
*The City's hills can offer some shade. But when drivers crest those hills, they can be blinded by the sudden burst of sunlight.
"You round the corner, get up that hill, and whang, it hits you," said Officer Shawn Chase, a spokesman for the CHP's San Francisco office.
Traffic safety experts advise motorists to use common sense. Clean your windshields. Wear quality sunglasses with polarized lenses and UV protection. Turn headlights on so oncoming motorists can see you as they're driving toward the sun.
Drive slower, even below the posted speed. It's against the law to drive at speeds in excess of road conditions. Use the same precautions and care as driving in other hazardous conditions, like fog or rain. If you can't see, don't drive.
And, if possible, change your driving route. Use north-south streets until you find an east-west road with lots of trees or taller buildings.
Glare, though it can suddenly blind you at an intersection or on top of a hill, should never come as a surprise, the CHP's Kohler said.
"Last time I checked," he said, "the sun goes down every day."
San Francisco Examiner
October 12, 1998
Ralph Bouwmeester, P. Eng.
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