Section 33.1-14-09-20 - Bottom blowoff and drain valves1. Each steam boiler having a capacity over twenty-five gallons [94.6 liters] must have a bottom blowoff connection fitted with a valve or cock connected to the lowest water space practicable with a minimum size as shown below: Minimum Required Safety Valve Capacity in Pounds of Steam/Hour | Steam Boiler Blowoff Piping Valve Size, Inches (Min.) |
Up to 500 | 3/4 |
501 to 1,250 | 1 |
1,251 to 2,500 | 1 1/4 |
2,501 to 6,000 | 1 1/2 |
6,001 and larger | 2 |
2. Each hot water boiler and each steam boiler having a capacity not exceeding twenty-five gallons [94.6 liters] must have a drain valve connected to the lowest water space practicable. The minimum size of this drain valve is three-quarter inch [1.9 centimeters].N.D. Admin Code 33.1-14-09-20
Adopted by Administrative Rules Supplement 2020-377, July 2020, effective 7/1/2020.General Authority: NDCC 23.1-16
Law Implemented: NDCC 23.1-16