Dear Street Smarts,
Q: I ride a bike and drive to and from work in the dark these days. Is it me or are cars headlamps getting brighter? Are more people driving with their brights on? Do all these pickups and SUV’s need headlamps and fog lamps on at all times? It is so bright, sometimes I have to stop and close my eyes or look away from the road while driving. Very dangerous. Perhaps, everyone getting the brightest lights available isn’t the best idea, especially in town when there are on-coming drivers and bicyclist sharing dark roads. It is blinding us. Is there a maximum lumens limit? Help me from going blind or crashing from the on-coming light assault. Thank you.
Andrew Dyer, Santa Cruz
A: The California Vehicle Code does not restrict the brightness of headlights but it does address topics such as positioning and when they should be used. Specifically, visit www.dmv.ca.gov and search for sections 24402, 24403, 24404, 24405, 24407 and 24409. That last section delves into the use of high beams.
I feel your eye pain. Once monthly, I make the long trip down I-5 to Southern California for family reasons. I drive overnight to avoid traffic. In my experience, the blinding headlights typically come from drivers who have their high beams on; however, I must agree some trucks – commercial as well as raised pickups – have some pretty bright lights.
But headlight brightness can be subjective, as everyone’s eyes are different.
“There are certainly differences in headlights – such as type, construction, height, angle – that can affect our perception of them, but there are also personal factors that have nothing to do with headlights,” said Chris Cochran, spokesman for the California Office of Traffic Safety. “For instance, as we age, our eyes are less able to adapt to rapid light level changes, to high contrast environments, and points of light become more spread out through aging lenses. Plus, being on a bicycle changes many of the dynamics.”
Complaints about headlight and auxiliary glare is highest among people, particularly women, ages 35-44, according to “Drivers’ Perceptions of Headlight Glare from Oncoming and Following Vehicles, ” a 2004 study by the National Highway Traffic Safety Administration.
“High intensity of headlights may extend the visibility of objects ahead, but it may also increase the discomfort that glare of the headlights may cause to drivers of other vehicles,” the study found. “Glare can also reduce visibility distances by reducing object contrast or causing drivers to avert their eyes from the roadway to avoid discomfort. The challenge for headlight designers and regulators is to maintain an appropriate balance between glare and visibility.”
While studies on this subject continue, there are some things drivers can do to reduce headlight glare and its impacts. Learn about “Driving in Darkness,” from the DMV at http://www.dmv.ca.gov/pubs/hdbk/driving_in.htm.