Safety Considerations for SPM Design & Operation

1. Standards & Risk Assessment

• Risk Analysis Frameworks:
  • ISO 12100: Identify hazards across operational phases—loading, cycling, maintenance.
  • ISO 14121: Apply hazard severity × exposure frequency × avoidance possibility.
• Functional Safety Control:
  • Use ISO 13849-1 or IEC 62061 to define safety integrity levels (PL or SIL).
  • Implement dual-channel safety PLCs or relays for E-stops, light curtains, etc.

2. Physical & Functional Safeguards

• Fixed & Interlocked Guards:
  • Comply with ISO 14120 for guard strength and secure mounting.
  • Ensure interlocks cut power to dangerous motion before access is granted.
• Presence Detection:
  • Install light curtains, safety mats, and area scanners on load/unload zones.
  • Devices must connect to safety relays with fault detection and auto-reset logic.
• Emergency Stops (ISO 13850):
  • Mushroom-head pushbuttons at every operator station and hazard point.
  • Confirm Category 3 or 4 fault tolerance in wiring with feedback to safety controller.

3. Control-System Safety Logic

• Safe Stop Categories:
  • Cat 0: Instant power off (e.g., cutter ejection).
  • Cat 1: Controlled stop before power cut (e.g., flywheel deceleration).
• Motion Safeguards:
  • Use two-hand controls, enabling switches, or hold-to-run joggers for setup mode.
  • Integrate speed monitoring to reduce movement speed in teach or access zones.

4. Electrical, Pneumatic & Hydraulic Safety

• Electrical Panel Compliance:
  • IEC 60204-1 standards: grounding, overload protection, labeled terminals.
  • Panel-door interlocks must trigger automatic safe-stop when opened.
• Pneumatics & Lockout:
  • LOTO-compatible valves with pressure-bleed indicators.
  • Emergency shutoffs for air/hydraulic supply, tagged and accessible.

5. Ergonomics & Operator Access

• Ergonomic Layout:
  • Maintain ≥500 mm safe clearance zones around manual workstations.
  • Place HMI at 1300–1500 mm height; ensure controls are within natural reach.
• Handling Support:
  • Vacuum grippers, lift-assist arms, or roller conveyors for heavy loads.
• Lighting:
  • ≥300 lux in active zones with diffused, glare-free lighting.

6. Training & Procedure Control

• Operator Certification:
  • Mandatory onboarding for machine operation and E-stop reset protocols.
  • Annual refreshers + skill assessments logged by HR/safety manager.
• Safe Work Permits:
  • Documented checklists for die changes, tooling swap-outs, off-cycle tasks.
  • Permit includes pre-operation checklist, isolation steps, and supervisor sign-off.

7. Testing & Validation

• Pre-Commissioning Safety Testing:
  • Validate all circuits, guards, and devices under simulated faults.
  • Log test results per ISO 13849-2 requirements.
• FAT & SAT Audits:
  • Factory and Site Acceptance Tests should include real-condition operation with operator training.

8. Maintenance & Lifecycle Safety

• Scheduled Inspections:
  • Daily: Guards, E-stop test, sensor response.
  • Monthly: Relay contact resistance, actuator travel checks.
• Incident Investigation:
  • All E-stop activations or interlock bypasses logged and analyzed.
  • “5 Why” root cause + corrective actions tracked for audit trails.
• Ongoing Risk Review:
  • New tooling or control logic requires full safety re-validation and risk reassessment.