What is the normal inside vertical height of a two-way manhole?

The standard inside vertical height of a two-way manhole is generally accepted to be not less than 7 feet and not more than 8 feet. This range is established to ensure adequate working space for maintenance and inspections, as well as to facilitate the safe movement of personnel and equipment within the manhole structure. Additionally, maintaining a height within these parameters helps to manage the flow and access to utilities such as sewer lines, stormwater systems, or other infrastructure housed within the manhole.

Other ranges, like those below 6 feet or above 8 feet, might compromise accessibility and safety. Specifically, a height less than 7 feet may limit operational efficiency, while a height exceeding 8 feet could lead to structural challenges or additional construction costs without significant operational benefits. Thus, the range of 7 to 8 feet is ideal for balancing functionality and practicality in two-way manholes.