Robot safety compliance is not optional. In the EU, a robot system without CE marking cannot be legally installed. In the US, OSHA standards and ANSI/RIA R15.06 govern industrial robot safety. Failure to comply creates unlimited civil liability in the event of injury. Yet many buyers — especially those importing Chinese robots — navigate safety compliance poorly, either over-engineering it (excessive cost) or ignoring it (serious legal exposure). This guide explains the actual standards, what they require, and what compliance costs.
Standards Overview
For Industrial Robots (Traditional)
ISO 10218-1: Robots and robotic devices — Safety requirements for industrial robots — Part 1: Robots
- Covers: The robot arm itself (manufacturer responsibility)
- Scope: Design requirements for safe robot construction
- Compliance: Robot OEM must certify; buyer verifies through documentation
ISO 10218-2: Robots and robotic devices — Safety requirements for industrial robots — Part 2: Robot systems and integration
- Covers: The complete robot cell/system (integrator and end-user responsibility)
- Scope: How the robot is integrated into a production environment
- Compliance: System integrator must conduct risk assessment and implement safeguards
ANSI/RIA R15.06 (US equivalent): Nearly identical to ISO 10218, adopted as the US national standard. Compliance with ISO 10218 satisfies ANSI/RIA R15.06.
For Collaborative Robots
ISO/TS 15066: Robots and robotic devices — Collaborative robots
- Covers: Power and force limiting (PFL) collaborative operation
- Key content: Body region pain threshold tables for quasi-static and transient contact
- Scope: Defines permissible contact forces and pressures for human-robot collaboration
- Status: Technical Specification (not full ISO standard); being incorporated into next ISO 10218 revision
ANSI/RIA R15.06-2012 (Annex A) addresses collaborative robot operation in the US context.
EU Machinery Directive / Machinery Regulation
For CE marking in the EU:
- Machinery Directive 2006/42/EC (current): Requires conformity assessment, technical file, and Declaration of Conformity
- EU Machinery Regulation 2023/1230 (effective 2027): Replaces Directive; adds requirements for autonomous machinery and collaborative robots
The Four Collaborative Robot Operation Modes (ISO/TS 15066)
ISO/TS 15066 defines four permitted modes for human-robot collaboration:
1. Safety-rated monitored stop (SMS): Robot stops when human enters collaborative workspace. Resumes when human leaves. No contact permitted while robot moves.
2. Hand guiding: Operator physically guides robot with force-sensing handle. Robot moves only when guided. Used for teaching and setup.
3. Speed and separation monitoring (SSM): Robot slows or stops based on proximity to human. Requires safety-rated distance sensors (laser scanner, ToF camera). Most complex; most productive.
4. Power and force limiting (PFL): Robot limits contact force to safe levels during normal operation. Allows continuous human-robot co-working. Requires biomechanical risk assessment per ISO/TS 15066 Annex A.
Most commercial cobots (UR, Fanuc CRX, KUKA LBR) implement PFL via joint torque sensing or current monitoring. PFL does not automatically mean no-fence required — a risk assessment must determine appropriate safeguards.
Risk Assessment: The Central Requirement
Both ISO 10218-2 and the Machinery Directive require a formal risk assessment for every robot system. The risk assessment must:
- Identify hazards: All hazards in the robot cell (mechanical, electrical, thermal, radiation, ergonomic)
- Estimate risk: Severity × probability × avoidability for each hazard
- Apply risk reduction: Elimination → substitution → safeguarding → information
- Verify residual risk: Document that remaining risk is acceptable
- Document: Risk assessment must be documented in the technical file
Risk assessment cost: $5,000–20,000 from a certified safety engineer, or free if done by a competent internal team. Not optional — this is the foundation of legal compliance.
Common mistake: Buying a CE-marked robot arm and assuming the entire cell is compliant. The robot arm CE mark covers only the arm. The complete system (cell) requires its own risk assessment and CE declaration.
Safeguarding Requirements for Industrial Robots
Perimeter Guarding (Traditional Requirement)
For robots operating above collaborative speed limits:
- Hard perimeter fencing: Minimum 1,800mm height, mesh size prevents arm reach-through
- Safety-rated interlocked gates: Open gate triggers safety-rated stop
- Safety light curtains: At access points; detect personnel entry
- Floor-mounted safety mats: Pressure-sensitive activation
Safety-rated (SIL/PLd) components are required. A standard photo-eye is not a safety light curtain. Category-rated safety devices (IEC 62061 SIL, ISO 13849-1 PLd or PLe) must be used.
Collaborative Robot Safeguarding
For PFL cobots with approved risk assessment, hard perimeter guarding may be eliminated, replacing with:
- Safety-rated speed/force limiting
- Area scanners (SICK, Keyence, Pilz) for zone-based speed reduction
- Soft guarding (signage, floor markings) for low-risk tasks
Note: PFL cobots still require risk assessment. A collaborative robot application that poses crush hazard from tooling, workpiece, or fixture is not automatically safe without guarding.
Safety-Rated Controller Requirements
Functional safety standards for robot controllers:
- IEC 62061: Safety of machinery — functional safety — SIL-rated systems
- ISO 13849-1: Safety of machinery — safety-related parts of control systems — PLd/PLe
Safety functions requiring certification:
- Emergency stop: PLd Cat.3 minimum
- Safety-rated monitored stop: PLd Cat.3
- Safe limited speed: PLd Cat.3
- Safe torque off: PLd Cat.3
All major robot OEMs (Fanuc, ABB, KUKA, Yaskawa) include safety-rated controller options. Chinese OEMs vary significantly — verify safety controller certification documentation before purchase.
CE Marking Process for EU Market
- Apply all relevant directives: Machinery Directive + Low Voltage Directive + EMC Directive as applicable
- Conduct risk assessment per ISO 12100
- Apply harmonized standards (ISO 10218-1/2)
- Prepare technical file: Risk assessment, design drawings, component specs, test records
- Issue Declaration of Conformity: Signed by responsible manufacturer/importer
- Affix CE mark to the machine
Notified body involvement: Not required for most standard robot machinery. Required only for certain high-risk categories under the new Machinery Regulation.
CE marking a Chinese robot system: If you import a Chinese robot without CE marking and integrate it for EU deployment, you become the manufacturer under EU law. Full compliance responsibility transfers to you. Either source CE-marked Chinese robots (Rokae, Estun, Efort all have CE) or factor CE compliance cost into your sourcing decision.
Compliance Cost Summary
| Requirement | One-time Cost | Recurring Cost |
|---|---|---|
| Risk assessment | $5,000–20,000 | Per system revision |
| Safety-rated E-stops/gates | $3,000–12,000 | — |
| Safety light curtains | $4,000–15,000 | — |
| Area scanners (cobot) | $8,000–20,000 | — |
| Safety PLC | $5,000–15,000 | — |
| Third-party safety audit | $3,000–10,000 | Recommended annually |
| CE marking documentation | $2,000–8,000 | — |
| **Total compliance** | **$30,000–100,000** | $3,000–10,000/year |
Safety compliance typically adds 15–25% to total robot system cost. Budget for it from the start — retrofitting safety after installation costs 2–3× as much.
Frequently Asked Questions
Does a CE-marked cobot need safety fencing?
Not automatically. CE marking on the cobot arm confirms the arm itself is designed for collaborative use. Whether fencing is required depends on the complete system risk assessment. If the application involves sharp tooling, heavy workpieces, or pinch points between robot and fixtures, fencing or other safeguards may still be required regardless of the cobot's CE status.
What happens if our robot cell is not compliant?
In the EU: illegal to place on market; subject to market surveillance authority enforcement, fines, and mandatory withdrawal. In the US: OSHA can cite non-compliant installations; unlimited civil liability in injury lawsuits. Practically, most facilities are not proactively inspected — but a single injury event triggers full compliance review. Non-compliant systems are virtually impossible to defend in litigation.
How often should robot safety systems be tested?
ISO 10218-2 requires functional testing of all safety functions at initial commissioning. Periodic testing frequency is determined by the risk assessment but annual testing of emergency stops, interlocks, and safety-rated speed monitors is standard practice. Test records must be documented.
Is ISO/TS 15066 mandatory?
ISO/TS 15066 is a Technical Specification, not a full ISO standard — not technically mandatory. However, it is the only published reference for contact force limits in collaborative robot applications, making it the de facto compliance reference. The next edition of ISO 10218 will incorporate ISO/TS 15066 content into a mandatory standard.
