Define the safe response

State exactly what must stop or be prevented when the guard opens, in every relevant operating mode.

Check whether locking is required

Compare time to reach the hazard with total hazardous run-down and consider process pressure, heat or other retained conditions.

Select an operating principle

Options include tongue-operated, hinge, coded magnetic or RFID non-contact devices, mechanical locking and trapped-key systems.

Reduce defeat motivation

Make legitimate tasks easy, avoid nuisance trips, use appropriate coding and position devices so simple bypass is difficult.

Engineer the door

Control sag, over-travel, impact and misalignment. A premium interlock on a weak or flexible gate will not be reliable.

Design diagnostics and fault response

Consider series connection, fault masking, device status and how maintenance will locate a problem without bypassing protection.

Validate

Test open, closed, locked, unlocked, reset, power loss, escape release and representative faults against the safety-function specification.

Project checklist

Points to confirm

  • Safety function defined
  • Stopping time known
  • Locking need assessed
  • Whole-body access considered
  • Escape release considered
  • Defeat motivation reduced
  • Door mechanics robust
  • Diagnostics planned
  • Validation test written

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.