On Tue, 27 Aug 2019 22:38:57 +0100, Max Demian wrote:

On 27/08/2019 17:25, Commander Kinsey wrote:
On Tue, 27 Aug 2019 17:13:18 +0100, Colonel Edmund J. Burke
wrote:

On 8/27/2019 9:03 AM, Commander Kinsey wrote:
Why is hi-vis clothing easier to see? What’s so special about the
colour?

Color, you ignorant limey.

So why isn't red, yellow, etc as easy to see? If you wear a bright red
tshirt, you aren't as visible as wearing a hi-vis jacket. Does it
convert all the wavelengths into one or something?

It's fluorescent. It converts ultraviolet (especially prevalent in the
dusk) into visible light.

I never realised this - there's more UV at dusk? Or just the same amount, and less visible light? I guess it's to do with diffraction of sunlight at the horizon?

Presumably mainly available in certain colours.

Why are they always yellow or green? Just to do with the chemicals in the dyes that can convert UV into visible?

Some, intended to be used at night, have strips that include glass or
plastic beads that reflect light (from torches or car headlamps) back in
the direction the light source is.

I once saw somebody being quite ingenious. He'd broken down and had no available light source from the vehicle (dead electrics presumably, no hazard lights etc). He'd put two hi vis jackets on the back, and every time a car approached, he flashed his torch at them.