Final answer:
The correct option for the valves that must relieve all excess pressure on a steam or high-pressure water boiler is a safety valve and/or an ASME-approved safety valve.
Step-by-step explanation:
The valves that must relieve all excess pressure on a steam or high-pressure water boiler are crucial to ensuring the safety and proper functioning of the boiler system. Depending on the type of boiler system, these can be categorized as safety valves or liquid relief valves. A safety valve is designed to automatically release pressure when the pressure inside the boiler exceeds a certain limit, preventing potential damage or explosions.
By contrast, a liquid relief valve is specifically designed to relieve pressure within systems that contain liquid rather than steam. In the case of a steam or high-pressure water boiler, ASME (American Society of Mechanical Engineers) standards generally require the use of an approved safety valve. These standards are in place to ensure that boilers operate safely and effectively within their designed pressure ranges.
Considering the provided option, which mentions an ASME-approved safety valve, the correct option for the valves that must relieve all excess pressure on a steam or high-pressure water boiler is: a) safety valve and/or an A.S.M.E. approved safety valve.