Unless this IH brush truck is going to explode, or deploy a chute to slow down, why the hell does it have the sign on the back to "stay back 500 feet"?

 

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500 feet is about 1 and 2/3rds foot ball fields long. There is no reason I can think of to stay that far away from a truck, unless it stinks, will explode, or has you mother in law in it

Steve looked into it, darn it. (he's such a great collaborator)

Here's what he found; 

Many state laws require 200-500 ft distance back only when lights and/or sirens are activated responding to, or parked on scene.

According to the California Vehicle Code Section 21706: "It is against the law to follow within 300 feet behind any fire engine, police vehicle, ambulance, or other emergency vehicle with a siren or flashing lights."

Easton is in Illinois, and according to the Illinois Vehicle Code Section 625 ILCS 5, Paragraph 11-1411: "Following fire apparatus prohibited. The driver of any vehicle other than one on official business shall not follow any fire apparatus traveling in response to a fire alarm closer than 500 feet or stop such vehicle within 500 feet of any fire apparatus stopped in answer to a fire alarm."

Why? I don't know for sure, but the most accepted explanation seems to be something along the lines of: "500 feet should give a driver who is paying attention enough reaction time to dodge anything that might fall off the truck, i.e. hose, tools, ladders, firefighters, boots, spike stripes, nozzles, helmets and so forth."

And more probable: "I've always understood it to be a holdover from the days when the men were riding tailboard - if a member fell off, 500' would give a following car plenty of time to swerve and avoid striking him."

For me, it makes sense to give them plenty of room when PARKED - especially for a hose truck, which, depending on the department, can carry up to 1,600 feet of hose that has to be unloaded and coupled together.