All boilers and unfired pressure vessels, including pressure retaining items listed in RCW 70.79.090(5), shall be safeguarded by safety pressure relief devices as specified in the applicable ASME Code or recognized standard. The pressure relieving device set pressure shall not exceed the boiler's or the unfired pressure vessel's maximum allowable working pressure unless allowed by the code of construction. These pressure relieving devices shall be installed per the applicable ASME Code or manufacturer's requirements. The outlet of the relief valve shall be run full size to a safe place and shall not induce undue stress on the valve. As an alternative they may be safeguarded by a fail safe pressure relief control system that is evaluated by a professional engineer knowledgeable with boilers and pressure vessels and accepted by the chief inspector.