When dismantling a boom, what should always be used?

When dismantling a boom, using suspended loads is crucial because it pertains to the weight and balance management of the boom during the dismantling process. When the boom is being taken down, it's important to control any loads that may be suspended from it to prevent accidental falls or shifts that could lead to serious injury or equipment damage. Proper handling and awareness of suspended loads ensure safety and stability during the operation.

The other options, while important in various contexts, do not directly relate to the specific task of dismantling a boom. Emergency signals are more about communication and warning others on site rather than the physical process of dismantling. Power tools may be necessary for certain tasks, but their use is not universally required or applicable in all dismantling scenarios. Personal protective equipment is critical for overall safety on the job site, but it does not specifically assist in the act of dismantling the boom itself.