How should electrical disconnect switches be installed for safety?

The correct choice emphasizes the importance of accessibility and security when installing electrical disconnect switches. By positioning these switches at an accessible location with a lockable cover plate, safety is prioritized, allowing authorized personnel to quickly disconnect power in emergency situations while also preventing unauthorized access. This is particularly crucial in environments where heavy machinery or high voltage equipment is present, as quick access to a disconnect switch can be vital in preventing accidents or mitigating damage.

In contrast, locating disconnect switches in a control room may seem convenient but can delay response time during an emergency. Similarly, placing them near the main electrical panel does not necessarily ensure safety if it remains easily accessible without a lockable feature. Installing them above the height of the boiler is impractical and could hinder emergency operations, making them difficult to reach when they are needed most.