What shape is the operating nut on a dry barrel hydrant typically?

The operating nut on a dry barrel hydrant is typically shaped as a pentagon. This specific shape is commonly used because it helps to prevent unauthorized access and tampering with the hydrant by requiring a special tool that fits the unique shape. A pentagonal design is also functional for providing a better grip and leverage for turning the nut, which is essential for operating the hydrant effectively.

While other shapes such as round, square, and hexagonal may exist in various applications or for different types of valves and hydrants, the pentagon is standardized for dry barrel hydrants, ensuring uniformity in tools used by firefighters and water distribution personnel. This standardization is crucial in emergency situations where quick access to a hydrant is necessary for fire suppression.