Name three products that MUST be a certain color. ie: Stop signs must be red.?

Oxygen: green cylinder

Nitrous oxide: blue cylinder

Helium: Yellow cylinder

Most of the younger people I know think Green Day is old. I find that funny since they came out when I was about 3. I grew up listening to older bands. Most of them tour today and I really love going to their concerts but I do get crap from teens about my music. They say only old people can go. I disagree many songs are appealing and sound better. It's also helpful that at my school, there is a club that is dedicated to the Beatles, we had celebration for John's Birthday. I find it encouraging knowing that many of my peers have some music in common because beyond the Beatles we really don't listen to the same bands. Classic rock strangely reunites people whom in the first place would never really have anything in common.

"MUST"? What's that mean? Per law, regulation, etc?

As far as I know, all major corporations have specific color definitions for their logos and packaging that must be followed by people creating those items.

Colors for safety use are fairly common - red = danger, yellow = caution, green = safe. Hence traffic lights and the use of colors in various warning/safety signs.

Car lights, at least in US, must by law follow some guidelines, e.g. red for brake lights, yellow for turn signals.

Port and starboard lights on boats/ships and navigation channel markers (both lights and paint color) follow international law.

I know there are regulations on airport beacons and lighting but don't know enough about it to specify.

Good question, that was fun. Is it a trick question, did I miss the point?

Stop Signs must be Red.

Skull and Cross Bones must be white on black background.

Fire Extinguishers must be Red (however, some are white).

Fire Trucks must be Red (However, some are white).

John Deere tractors must be Green (However, some are green and yellow).

Toilet Paper must be white (However some of it has things like jokes printed on it in black).

Ketchup must be red.

Mustard must be yellowish (Some is golden - hint of brown).

Plain Milk must be White or people won't buy it.

Caution Signs must be Yellow (But some are not).

Yahoo's Logo must be Red.

In the places I've lived, fire trucks have always been chartreuse! Anyway, illuminated "EXIT" signs that are placed over an exit are to be red, those that point to an exit are to be green (OSHA regulations). But more often than not, builders disregard those rules. Also, gas cans are red and traffic cones are fluorescent orange.

brake lights are always red, at least legal brake lights

coca cola is always in a red can

stop lights are always red yellow and green

School bus yellow.

Blue light specials.

Non-potable water valve. Purple. That's water which can't be drank by humans. They use it in irrigation.

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Transmission Fluid must be Red

Anti-Freeze must be Green

Windshield Washer Fluid must be Blue

yeild signs have to be yellow.

sun has to be red orange or yellow

blood is blue when not touching oxygen red when touching oxygen purple when dry

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