Despite popular belief, not all fire hydrants are red. In fact, to a firefighter, red is the last thing they should be. That's because in parts of the U.S. and Canada, the color of a fire hydrant—or, specifically, its top and nozzle cap—is usually a sign of its flow rate and water pressure. This lets firefighters know whether a particular hydrant will provide them with the amount of water they'll need to put out the fire they're facing. It also tells them what size hose to use, how best to pump the water, and a variety of other essential information. A blue top means that the hydrant will produce a great flow—at least 1,500 gallons per minute. Green means the hydrant will produce slightly less, orange less than that, and red means the hydrant will produce less than 500 gallons per minute, which is probably not enough to get the job done.
These colors are laid out in a National Fire Protection Association standard known as NFPA 291. But this is just a recommendation, and as a result, not all municipalities or fire departments follow it. In fact, individual state and city regulations sometimes piggyback or contradict the regulation, leading to problems. For example, a Texas law requires all "nonfunctioning" fire hydrants—that is, ones that pump less than 250 gallons per minute—to be painted black. Many rural areas can't necessarily guarantee a dependable flow rate, so they end up painting all of their hydrants black to avoid liability, leaving firefighters unable to tell them apart. Learn more about fighting fires with the videos below.