page_title: Fire hydrant
section_title: Other uses
hierarchical_section_title: Fire hydrant / Operation / Other uses
caption_attribution_description: English: Reduced pressure zone device (also known as reduced pressure principle assembly) connected to a fire hydrant at a construction site.
context_page_description: A fire hydrant is a connection point by which firefighters can tap into a water supply. It is a component of active fire protection. Underground fire hydrants have been used in Europe and Asia since at least the 18th century. Above-ground pillar-type hydrants are a 19th-century invention.
caption: A reduced pressure zone device is used to prevent back-flow when supplying water to a construction site
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