ISO 10218: Mandatory Safety Standard for Robots
Every industrial robot must undergo risk assessment before operation — it's not optional. ISO 10218 mandates this. For welding robots especially, hazards extend beyond mechanical collision to arc radiation, welding fumes, heat, and UV — making risk assessment more complex than standard pick-and-place systems.
This guide walks through complete risk assessment for a real welding cell (2 FANUC robots) per ISO 10218-1 and ISO 10218-2.
ISO 10218-1 vs ISO 10218-2: What's the Difference?
| Aspect | ISO 10218-1 (Robot) | ISO 10218-2 (Robot System) |
|---|---|---|
| Who | Robot manufacturer (FANUC, ABB, KUKA...) | System integrator |
| Scope | Robot manipulator itself | Entire cell: robot + gripper + positioner + fence |
| Focus | E-stop, speed monitoring, force limiting | Risk assessment, safeguarding, layout |
| Responsibility | Manufacturer | Integrator + end-user |
If you're a system integrator in Vietnam, ISO 10218-2 is your responsibility. FANUC robots already comply with Part 1. But when you mount torch, position 2 robots, add positioner, design layout — you create new system requiring own risk assessment.
Example Risk Assessment: Welding Cell with 2 FANUC Robots
Cell Description
Two FANUC ARC Mate 100iD robots with 2-station turntable positioner:
- Robots: 12kg payload, 1420mm reach each
- Positioner: H-type, 2 stations (weld at station A, load/unload at B)
- Torch: Lincoln Electric MIG/MAG
- Workpiece: Steel motorcycle frames
Step 1: Hazard Identification
Mechanical hazards:
- M1: Impact — arm collision with worker
- M2: Crushing — trapped between robot and positioner
- M3: Cutting — sharp workpiece edges
- M4: Entanglement — clothing caught in positioner
- M5: Splatter — weld splatter outside cell
Thermal & Radiation:
- T1: Arc flash — eye damage from arc light
- T2: Burn — hot workpiece (>300°C) after welding
- T3: UV — ultraviolet from arc (5m radius)
Chemical:
- C1: Welding fumes — Mn, Cr, Ni oxides
- C2: Shielding gas — CO2/Argon accumulation
Electrical:
- E1: Shock — contact with torch/workpiece during welding
- E2: Arc fault — damaged welding cable
Step 2: Risk Estimation
For each hazard:
- Severity (S): 1-5 scale (1=minor scratch, 5=death)
- Probability (P): 1-5 scale (1=rare, 5=daily)
- Exposure (E): 1-4 scale (1=<1% time, 4=>50% time)
- Risk = S × P × E
Example scores for welding cell:
| Hazard | S | P | E | Risk | Level |
|---|---|---|---|---|---|
| M1 — Impact | 4 | 2 | 3 | 24 | HIGH |
| M2 — Crushing | 5 | 2 | 3 | 30 | VERY HIGH |
| T1 — Arc flash | 4 | 3 | 3 | 36 | VERY HIGH |
| C1 — Welding fumes | 3 | 4 | 4 | 48 | CRITICAL |
| E1 — Shock | 4 | 2 | 2 | 16 | MEDIUM |
Threshold: Risk <12 acceptable. Anything >12 needs controls.
Step 3: Risk Reduction
Hierarchy of controls (in order of preference):
1. Inherent Safe Design
- Reduce overlapping workspace zones
- Round sharp edges on fixtures
- Lower positioner rotation speed (<10 rpm)
2. Safeguarding (Physical Barriers)
Light Curtain (Rèm quang):
- Model: SICK C4000 Advanced (Type 4, SIL 3)
- Resolution: 14mm (detects fingers)
- Height: 1800mm (covers entry door)
- Function: Shuts down robot when intrusion detected
Safety Mats:
- Coverage: 2m × 1.5m in front of load/unload station
- Function: Allows positioner rotation only when operator present
E-Stop Buttons:
- Locations: Corners of cell entry, teach pendants, control panel
- Type: Category 0 stop (immediate power cut)
- Reset: Must twist button + press Reset on panel
Speed and Separation Monitoring (via FANUC DCS):
- Weld zone: 100% speed when cell closed
- Overlap zone: 250 mm/s
- Near operator: 0 (immediate stop)
3. Supplementary Measures
| Hazard | Control | Details |
|---|---|---|
| T1 — Arc flash | Welding curtain | UV-resistant vinyl, Grade 8 |
| T2 — Burn | Heat-resistant gloves | Operator uses tongs, no direct contact |
| C1 — Fumes | Local exhaust ventilation | >0.5 m/s at weld point, HEPA filter |
| C2 — Gas leak | O2 sensor + fan | Alarm <19.5% O2, auto-ventilation |
| M5 — Splatter | Splash shield + PPE | Safety glasses mandatory 5m radius |
Step 4: Performance Level (PL) and SIL Verification
Use SISTEMA tool (free, IFA Germany) to calculate PL per ISO 13849-1:
| Safety Function | PL Required | Reason |
|---|---|---|
| E-stop | PL d | High severity, frequent exposure |
| Light curtain | PL e | Direct hazard protection |
| Speed monitoring | PL d | Continuous monitoring |
| Safety gate | PL d | Prevents access during operation |
Each control must achieve required PL through redundancy, diagnostics, or proof-testing.
Step 5: Validation and Testing
- Dry run: Test with no workpiece, operator manually triggers each hazard
- Load test: Run with actual workpiece, various scenarios
- Annual re-assessment: Review hazards, update risk matrix
- Incident tracking: Log near-misses, adjust controls if needed
Documentation Required
- Risk assessment report (with hazard register, risk matrix)
- HAZOP analysis
- Control measures and effectiveness evidence
- Operator training matrix
- Emergency procedures
- Maintenance schedule
Common Mistakes to Avoid
- Forgetting secondary hazards: Weld splatter, fumes are serious
- Under-estimating probability: Workers find creative ways to bypass safety
- Ignoring residual risk: Even with controls, some risk remains
- No periodic review: Risks change as equipment ages
- Poor documentation: Can't defend in case of incident
Key Standards Reference
- ISO 10218-1:2024 — Robot safety requirements
- ISO 10218-2:2024 — System integration
- ISO 13849-1:2023 — Safety of control systems
- ISO/TS 15066 — Collaborative robots (if using cobots)
- ISO 12100 — General machinery safety
Takeaway
Risk assessment isn't bureaucratic overhead — it saves lives and protects your company from liability. Invest time upfront to get it right. A proper risk assessment documented thoroughly is your best defense in case of incident.
