What is a crucial consideration when operating machinery with belts?

When operating machinery with belts, ensuring that guards are always in place is a crucial consideration for safety. Guards serve as a protective barrier that prevents accidental contact with moving parts, which can cause serious injuries. These safety devices help to minimize the risk of entanglement or pinching, which is particularly important given the high speeds and forces involved in machinery operation.

While the other options touch on different aspects of belt maintenance and operation, they do not prioritize the safety that guards provide. Loose belts can lead to inefficiencies and may even increase wear on machinery or cause belts to slip, while reusing old belts comes with risks, as wear and tear can compromise their integrity. Allowing hands to be close to the belt during operation poses a significant risk of injury. Therefore, the presence of guards is paramount to ensure safe operation and protect personnel working near machinery.