PDFWAC 296-826-30015
Nonrefrigerated stationary containers.
(1) You must construct and test containers according to the Unfired Pressure Vessel Code.
(2) You must make sure the minimum design pressure of the container is 250 psig.
(3) You must make sure all containers with a capacity exceeding two hundred fifty gallons are constructed to meet one or more of the following:
(a) Stress relieved after fabrication according to the Unfired Pressure Vessel Code;
(b) Have stress relieved cold-formed heads;
(c) Hot-formed heads.