The specifications, models and dimensions of outdoor fire hydrants may vary in different countries and regions, mainly because of the different standards and requirements in different places. However, I can provide some more general information.
Outdoor fire hydrants are usually divided into two types: above-ground and underground. Above-ground fire hydrants are generally common and are installed directly above the ground for easy connection by fire trucks. Underground hydrants are installed below ground level and require a lid to be opened to be seen and used.
Common specifications and models.
Caliber: The caliber of outdoor fire hydrants is generally DN100, DN150, etc., where DN represents the nominal size of the diameter, and the unit is millimeters (mm). DN100 means a nominal diameter of 100mm, DN150 is 150mm.
Interface specifications: Interface specifications usually follow local fire protection standards, for example, in the United States, the interface may be NH (National Hose) or NST (National Standard Thread) standards, and the caliber is generally 25 inches (about 63.)5mm）。In Europe and some other regions, interfaces may follow BS (British Standard) or DIN (Deutsches Institut für Normang) standards.
Working pressure: The working pressure of outdoor fire hydrants is generally 10MPa (about 10bar) to 1between 6MPa (about 16 bar).
Size. Above-ground fire hydrants: the height is generally between 750mm and 1200mm, which can ensure the convenience of operation.
Underground fire hydrants: The size mainly depends on the installation depth and the size of the cover, usually the diameter of the cover is between 200mm and 300mm.
Precautions. When choosing a hydrant, consider the local climate conditions (e.g. whether a freeze-proof hydrant is required).
The location and quantity of installations should follow local fire codes and standards.
It is very important to regularly inspect and maintain fire hydrants to ensure that they can be used properly in case of emergency.
For specific specifications and dimensions, please refer to your local fire code and manufacturer's product instructions.