Scientists studying effects of glaring HID headlights

Dear Tom and Ray: I'm writing about overly bright headlights. I have been calling them halogen headlights, but I saw in another response you gave that they are technically xenon or high-intensity discharge headlights. Well, I'm writing to let you know that when a car is coming at me with those lights, it feels like lasers are piercing my retinas! I detest those things. And yes, I do put my brights on when a car approaches me with those on. I doubt they get the message, but it makes me feel better. I have spoken to others who have this same loathing for and physical reaction to those xenon/HID lights. My question: Do you know of a grassroots movement that is opposed to them?

Chris

Tom: There is one grass-roots effort that we know of, Chris. It's called the Stop High-Intensity Discharge Headlights Evenings After Dark, or SHIDHEAD.

Ray: Actually, there's a real effort underway to understand the particular problems with HID lamps, because so many people have complained -- and continue to complain -- about them.

Tom: Scientists at the National Highway Traffic Safety Administration have been studying the issue of "glare" for several years now in response to overwhelming complaints from the public. And as they wrap up their research, the two issues they're focusing in on are the xenon/HID technology itself and the mounting height of headlights.

Ray: In terms of the mounting height, there are people who believe that car makers are allowed to mount headlights too high, and that lowering the height requirement for headlamps might really help cut down on glare from oncoming traffic.

Tom: The other issue they're looking at is whether there is a particular problem with the blue HID bulbs you mention, Chris. Is the problem that they simply produce too much light? Or is it the type of light they produce?

Ray: There's evidence that light containing a lot of shortwaves (like blue) produces more discomfort in the human eye than longer light waves (like red or orange).

Tom: NHTSA is studying the data, and hopes to propose some new rules by the end of 2005. When they do, we'll let you know here in the column, because at that point they'll want to hear from the public. If enough people support the rules, they'll go into effect and you'll eventually see an improvement on the roads. In the meantime, you'll just have to do the best you can and squint, Chris.