Minn. R. agency 151, ch. 5225, BOILER SAFETY, pt. 5225.4900
On all stationary boilers, when the allowable working pressure exceeds 100 pounds per square inch, each bottom blowoff pipe must have two slow-opening valves, or one slow-opening valve and a quick-opening valve or a cock complying with Section VII of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code. The quick-opening valve, if used, must be located nearest the boiler.
The bottom blowoff pipes of every traction and/or portable boiler must have at least one slow-or-quick-opening blowoff valve or cock conforming to the American Society of Mechanical Engineers Boiler and Pressure Vessel Code Section VII requirement.
Blowoff valves and cocks must be located in a convenient and accessible place, using extension valve stems if necessary to secure safe operation.
Minn. R. agency 151, ch. 5225, BOILER SAFETY, pt. 5225.4900
Statutory Authority: MS s 175.171; 183.42; 183.44; 183.465; 183.466; 183.54; 326B.958; 326B.964; 326B.966; 326B.982