What is the minimum separation required between supply and communications facilities in joint-use manholes and vaults for voltages between 15,001 to 50,000 volts?

• A. 12 inches
• B. 6 inches
• C. 3 inches
• D. 9 inches

Answer: (D)

The minimum separation required between supply and communications facilities in joint-use manholes and vaults for voltages between 15,001 to 50,000 volts is 9 inches. This standard is important for ensuring the safety of both the electrical and communications systems, as it helps to prevent electrical interference and reduces the risk of electrical hazards such as short-circuits or cable failures. Maintaining this separation contributes to the reliability of the systems and protects personnel who may be working in these joint-use facilities. Such regulations are designed based on industry best practices, which take into account the potential for electrical fields and the need for physical clearance to ensure the systems do not adversely affect one another.