Fixed guarding
A fixed guard is held in place so removal requires a tool. It offers high reliability, low control complexity and clear separation, but poorly designed removal can make maintenance difficult.
Interlocked movable guarding
An interlocked guard is connected to the safety control system. Opening it causes the defined safe response and hazardous operation is prevented while it remains open.
Guard locking
Guard locking retains the door or gate until dangerous movement, pressure, temperature or another condition has reached a safe state. Escape release may be required for whole-body access.
Access frequency
Frequent access normally favours a well-engineered movable guard or non-contact protective device. Rare access favours fixed guarding, provided removal and replacement can be completed safely.
Stopping time
A basic interlock does not physically stop a person opening the guard. Where run-down exceeds the time to reach the hazard, guard locking or increased distance is commonly needed.
Defeat and reliability
Poorly aligned doors, nuisance stops and awkward tasks encourage defeat. Use robust mounting, appropriate coding, good diagnostics and an access method that supports the work.
Project checklist
Points to confirm
- How often is access required?
- Can the task be moved outside the guard?
- How quickly does the hazard stop?
- Is whole-body entry possible?
- Could someone be trapped inside?
- Is process containment needed?
- How will the guard be inspected?
- What happens after the guard closes?
How Oxford Machine Guarding can help
We can survey the equipment, define the guarding and safety-system scope, develop the design, supply and install the solution, and provide testing and handover records appropriate to the agreed project boundary.
This guide provides general technical information. It is not a substitute for a machine-specific risk assessment, legal advice or verification by the responsible dutyholder.
