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erth64net
11-18-2007, 09:34 PM
At the Thursday parade, there were a number of folks using blue LEDs and blue electroluminescent wire. Though there were at least a half-dozen cops around, I never observed anyone being asked to turn off or otherwise remove their blue lights.

Blue seems such an effective color for grabbing attention. Since I couldn't find anything in ORS prohibiting blue reflective material, I'm using that to help grab attention at night. Though Oregon's law is pretty clear regarding blue lights; to quote ORS 816.350.4 "...Vehicles operated by a police officer and used for law enforcement may be equipped with any type of police lights, but only these vehicles may be equipped with blue lights." (source: http://www.leg.state.or.us/ors/816.html )

Is there an exception for cyclist that I've missed, are bicycles not actually classified as a "vehicle" under ORS, or are blue lights in-fact illegal for cyclist to use?

K'Tesh
11-18-2007, 10:08 PM
At the Thursday parade, there were a number of folks using blue LEDs and blue electroluminescent wire. Though there were at least a half-dozen cops around, I never observed anyone being asked to turn off or otherwise remove their blue lights...


816.250 Police lights. Each of the following is a requirement for police lights as described:
(1) Police lights may be blue, red, yellow, amber or white.
(2) Police lights may be revolving or stationary-type flashing lights.
(3) Police lights shall be visible from a distance of not less than 1,000 feet under normal atmospheric conditions at night.
(4) Police lights may include one or more lights.

As one of the winners of the Best Lit bikes (using blue lights), this is what I understand...

The issue about blue lights on vehicles relates to FLASHING blue lights. The Down Low Glow Lights (DLG) from http://rockthebike.com and the Cold Cathode lights from http://www.vibelights.com have steady (not flashing) blue lights.

The following is taken from Rock the Bike's website:

"In practical, daily use, police officers do not bother Down Low Glow customers, because they respect bicyclists who take safety seriously."

What's more Blue is SUCH a Cool Color! :D

http://farm3.static.flickr.com/2143/2039831218_b6f5a20584.jpg

Light the Bike, See the Bike!
K'Tesh

wyeast
11-18-2007, 11:34 PM
816.250 Police lights. Each of the following is a requirement for police lights as described:
(1) Police lights may be blue, red, yellow, amber or white.
(2) Police lights may be revolving or stationary-type flashing lights.
(3) Police lights shall be visible from a distance of not less than 1,000 feet under normal atmospheric conditions at night.
(4) Police lights may include one or more lights.


Except those passages use the word "May" as opposed to "Shall". It's a very distinct interpretation between the two. (those who are familiar with concealed weapons permitting run into this as well from state to state)

So the Police lights may be flashing, but not necessarily. However, as far as I can tell, most of the other passages referring to lights that are allowed on "civilian" motor vehicles generally phrase that they shall be white, amber, yellow, or red.

So for the most part, I believe it's mainly specific officer discretion that they don't bother to bust someone with EL wire on a bike, because simply put, it doesn't resemble a police vehicle in any way. However, I don't know if the same could be reliably thought with a bike that had a solid bank of blue LED's facing the front.

nuovorecord
11-20-2007, 12:25 PM
I'm not a physicist, but I took a class in college. :)

I seem to recall that blue light simply is not as visible as white and it wouldn't seem to be a good choice for a bike light. Blue doesn't have the contrast against a dark background that white does.

Try typing blue letters against a black background on your computer to get an example.

Blue might look cool, but I think you'd be better off with a white light. But, if I'm wrong, feel free to show me the error of my thinking!

wyeast
11-20-2007, 02:33 PM
Another interesting anecdote - I happened to approach an emergency vehicle on the left shoulder along a long straight stretch of freeway (tho' honestly I can't recall if it was SR14 or I5 where it parallels Barbur)

In either case, I saw the flashing red light from a looong ways off. It wasn't until I was *much* closer, easily less than half the distance, that I realized it was a police motorcycle when I could finally see the blue flashing LED's.

So I'd be inclined to agree that blue is distinctive up close, but doesn't stand out at a distance.

Donald
11-28-2007, 01:40 AM
Check out the MundM test.

http://cosmos.ucdavis.edu/2003/cluster%202/James%20Ide/James_Ide_Cluster2.pdf

Not sure how the test parameter of using "colorless water" instead of, say, a gas such as air, bends the experiment away from this conversation.

But I thought it was cool.

Conflicting (or not, if you consider air vs. water) notes here:

http://www.madsci.org/posts/archives/1999-10/939051861.Eg.r.html

And that's enough of the internets for tonight.

I just got a pair of these "gummy" lights (one red, one white) and I'm going to install them on the back of my helmet.

agramsci
11-28-2007, 11:10 PM
I think cops are not likely to bother you much about blue lights, flashing or not, unless they think there is some clear and present danger posed, or you give them some other pretext to. Still, I would tend to play it safe and use a different color. Why create any doubt or pretext for any harassment at all?

As far as visibility (or the more technically precise term, "conspicuity") goes, there is relevant research published on that subject here: http://tinyurl.com/2navzh
The conclusions? Blue light is thought to have poor response time (time it takes to be noticed among other noise). On the other hand, it has some practical advantages, for example: it was the most visible of all colors examined when viewed peripherally. Blue also produces the least distracting glare and least tends to exacerbate "disability glare" (ie, less likely to make it harder to view objects in its midst).

In "real world" applications as found by the paper, blue lights tend to produce less lumens of total light output, and according to the photopic response curve (http://www.electro-optical.com/whitepapers/candela.htm) requires proportionally more power to elicit an equal sensory response.

Given the conventional association of blue with emergency services, which the paper verified is strongly established, this paper suggested that the safest bet for other users would be a mix of different colors, ideally alternating (eg, amber/red).