LAS VEGAS - A viewer asks what the purpose is of blue lights that sit in the middle of valley roads.
Those blue lights are raised pavement markers or RPMs. They are used to mark the locations of nearby fire hydrants.
Emergency responders use them to quickly locate a fire hydrant, especially if something such as a parked car or overgrown foliage blocks the hydrant from their vision.
The markers aren't actually lights. They are reflectors. They reflect headlamps back to the vehicle operator, allowing the operator to easily spot them.
All of southern Nevada's jurisdictions use these RPMs.
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