Manufacturing Skill Standards Council (MSSC) Safety Assessment Practice Test

What type of machine guard prevents a machine from operating if the guard is not securely in place?

1. Fixed

2. Interlocked

3. Adjustable

4. Automatic

The correct answer is: Interlocked

An interlocked machine guard plays a crucial role in maintaining safety by ensuring that the machine cannot operate unless the guard is in a secure position. This type of guard is designed to be connected to the machine's control system, creating a safety mechanism that stops the machine’s operation if the guard is removed or not properly engaged. By employing interlocking technology, this guard helps prevent accidental exposure to hazardous areas of the machine, effectively reducing the risk of injury. For example, if a worker needs to access the machine for maintenance or adjustment, the removal of the interlock would immediately halt operation, thereby protecting the operator. In contrast, a fixed guard is permanently attached, providing protection but does not incorporate the safety feature of stopping machine operation when tampered with. Adjustable guards may change position to accommodate varying operations but do not intrinsically prevent the machine from functioning without being in place. Automatic guards typically engage and disengage automatically based on the process but do not share the same direct connection to machine operation as interlocked guards. Thus, the interlocked guard stands out as the correct safety solution among the choices provided.