Which option would not be part of releasing stored energy?

Releasing stored energy is an important safety consideration in control systems and machinery operation. The process involves safely managing energy that may be stored in various forms, such as potential energy in springs, pressure in pneumatic or hydraulic systems, or energy stored in a loaded machine.

When considering the options, attempting to start the machine does not actively contribute to the release of stored energy. Instead, it potentially engages the mechanical systems of the machine and can lead to the release of energy when the machine is operated. However, this is not a method of release; rather, it might be a scenario where energy is still retained until the machine reaches operational status.

In contrast, closing valves is a method often used to isolate energy sources, while releasing spring tension and releasing steam pressure are direct actions aimed at safely dissipating stored energy in their respective systems. Each of those actions directly pertains to managing energy control measures, whereas starting the machine involves engaging its operational dynamics without specifically addressing the need to release energy beforehand.