To easily form a knob while increasing the strength in a door structure of a fire hydrant apparatus.

The fire hydrant apparatus 100 has a fire extinguisher door 6c, which is not indicated, inside a housing 101 to be opened when a fire extinguisher is used. A horizontally or vertically crossing reinforcing member 12 whose section is approximately U-shaped is disposed on the back surface of a door panel 11 of the fire extinguisher door 6c, and an opening 13 of the door panel 11 is formed at the position corresponding to the reinforcing member 12 to be used as a knob. Accordingly, the strength of the door panel 11 can be increased, and at the same time, the knob can be formed by such a simple structure as the space inside the U-shaped section is used as the knob.