From a terminology standpoint, jph2's post shows a color closest to lime - as found in the fruit section at the grocery store, or growing from a lime tree - rather dark green with little, if any, yellow appearance. If you want a "yellow lime", then you buy what's known as a "lemon." Yes, I know they have different tastes. And that's what's going on here - different tastes. I'm not trying to be a wise-guy (remember, there's a difference between a wise man & a wise guy). I'm trying to point out that "lime-green" and "lime-yellow" seem to be considered the same color as regards paint.
The lime-yellow discussion started in the '70's through a study published by an eye doctor - see the article below (and the link afterwards for more information). Yes, it's old information, and some of it has been, and continues to be, disputed. But the study referenced lime-yellow - nothing was said about lime-green. The term may have begun when folks who didn't like lime-yellow called it "slime green" - I don't know how the reference changed from lime-yellow to lime-green. Heck, as you can see in the link below, a 1959 study concluded "Golden yellow . . . [is] the most easily visible color for both normal and color deficient groups under all testing conditions." Maybe combining yellow and green paint in such proportions at that time was considered a criminal infringement on the already-existing chartreuse. I don't know what "golden yellow" is supposed to look like. I remember a similar discussion about "chrome yellow."
Some photographs don't accurately portray lime-yellow. I'm not saying the photographer doesn't know how to take a picture. I'm just saying that the surrounding light when the picture was taken, or whether a flash was used - or for reasons about which I'm clueless - sometimes lime-yellow in a photo just isn't an accurate portrayal of its actual appearance - sort of like Drew Carey as Hamlet.
Yes, I know there are those who just don't like it - simply don't like it - want nothing to do with it - believe an emergency services vehicle, particularly a fire truck, should be red (or whatever color they prefer). But if - IF - an injury is prevented, or a life saved, because somebody saw, and avoided a collision with, an emergency services vehicle because it's lime-yellow, I find it difficult to say "never" to such a color, or "always" to another darker color just because "that's the way it's always been." Remember, lots of wasted effort was put into hand-operated pumpers challenging the new technology of steam, and lots of folks wanted to continue to feed horses rather than use a vehicle powered by explosive gasoline. Yes, those issues were easily quantified - steam was readily seen as having more power than a bunch of men frantically raising and lowering handles, and when the four legs of a horse, even when used in multiples of four, were outrun by a vehicle with four wheels, the evidence was visible. And that's what the lime-yellow study was all about - visibility. But some still don't agree. Some because of "tradition." Others because they just don't like the color. Still others don't believe the conclusions of the study. And some rely on the tongue-in-cheek statement that a "green" fire truck just isn't "ripe." That said, airport firefighting apparatus is lime-yellow, as specified by the Federal Aviation Administration. And that may just be another proof for some that, just because the "government" says so, that "don't make it so." (Some also see it as a way of ensuring that airport firefighters don't mistake a fire truck, painted lime-yellow, for a 767, painted, well, mostly, not lime-yellow.)
I've included a faded example of green - lime or otherwise - I don't know what American LaFrance called it. Maybe it was "emerald", to coincide with the name of, apparently, the original buyer. I took the picture with my handy-dandy Canon digital on a very sunny July day. Yes, I see what appears to be a blue tinge on the panel. And yes, it appears the rig was once red. But just as the green paint on this truck can't be accurately called "lime-yellow", neither can it be accurately called "lemon-green" because, well, it isn't. Notice I didn't say "lime-green." Doing so is like saying "tooth dentist" - there is no other type of dentist. So it is with limes. They're, well, green. Granted, varying shades depending upon their current development, but limes are green and lemons are yellow. When those colors are combined in proportions related to the study, they're historically called . . . wait for it . . . "lime-yellow."
I'm retreating now, into my dungeon, to experiment with the visual possibilities of combining avocado (peeled & whole) with banana peels. I'm unaware of any prohibitions of this sort by the Federal Aviation Administration. If you see my picture on the wall of post offices, please tell them I meant well and that my only hope was to be able to register for Medicare next year.
Why Lime-Yellow Fire Trucks Are Safer Than Red
Red may be the traditional color of fire engines, but human factors and ergonomics research finds that lime-yellow fire vehicles are less likely to be involved in accidents.
Picture a fire truck and you are likely to see red - fire engine red. But when it comes to safety, human factors and ergonomics research paints a different picture. Much of human factors and ergonomics research relies upon psychological research done on human visual and auditory perception. This research shows that because the color-transmitting cones in our eyes don't work well in the dark, some colors are easier for us to see at night. We are most sensitive to greenish-yellow colors under dim conditions, making lime shades easiest to see in dim lighting.
Researchers Stephen S. Solomon and James G. King (volunteer firefighters themselves) were aware of these perceptual differences when they analyzed accident data from the Dallas Fire Department. In the 1970's and early 1980's, the City of Dallas started replacing its all-red fire vehicles with lime-yellow fire vehicles with white upper cabs. After the early 1980's, the fire department bought red vehicles with white cabs. During their four year study published in 1995, Solomon and King found that the risk of a visibility-related, multiple-vehicle accident may be as much as three times greater for red or red/white fire pumpers compared to lime-yellow/white pumpers. The results also show that when lime-yellow/white fire emergency vehicles are involved in an accident, the likelihood of injury or towaway damage is less than for red or red/white vehicles involved in an accident. An earlier study by Solomon involving nine cities and 750,000 fire-vehicle trips found that lime-yellow fire pumpers were half as likely as red fire pumpers to be involved in intersection accidents.
The National Fire Protection Association (
NFPA) estimates that in 2001 there were 14,900 motor vehicle accidents involving fire department vehicles that were responding to or returning from incidents. These accidents - which included vision-related accidents involving red fire vehicles - often resulted in serious injuries to firefighters and other motorists.
Applying the findings of human factors and ergonomic research, the Federal Aviation Administration has converted their aircraft rescue and fire-fighting fleets to lime-yellow. Many communities are also switching to lime-yellow fire vehicles, resulting in fewer accidents and lives saved.
Solomon, S. S., & King, J. G. (1995). Influence of color on fire vehicle accidents. Journal of Safety Research, Vol. 26, pp. 41-48.
Solomon, S. S. (1990). Lime-yellow color as related to reduction of serious fire apparatus accidents: The case for visibility in emergency vehicle accident avoidance. Journal of the American Optometric Association, Vol. 61, pp. 827-831.
American Psychological Association, October 23, 2003
Same song, different verse:
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