Robot Safety Standards

Why This Matters

Robot safety standards aren't just bureaucratic paperwork—they're the foundation of every design decision you'll make when humans and machines share space. You're being tested on your ability to understand why certain safety measures exist, how risk assessment drives design choices, and when different standards apply. Whether you're designing an industrial workcell or a personal care robot, examiners want to see that you can connect specific standards to their underlying safety principles.

These standards demonstrate core robotics concepts: risk hierarchy, functional safety, and human-robot interaction protocols. Don't just memorize standard numbers—know what category each falls into (industrial vs. collaborative vs. personal care), what level of the safety system it addresses (design, control, or operation), and how standards work together to create layered protection. When an exam asks about collaborative robot safety, you should immediately connect ISO/TS 15066 to the broader ISO 10218 framework and explain why cobots need different rules than caged industrial arms.

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Industrial Robot Standards

These standards govern traditional industrial robots—high-speed, high-payload machines that typically operate in separated or guarded workspaces. The core principle is physical separation: keep humans out of the robot's operating envelope during automatic operation.

ISO 10218: Industrial Robot Safety Requirements

• The foundational international standard—establishes safety requirements for design, manufacturing, and integration of industrial robot systems worldwide
• Risk assessment methodology forms the backbone, requiring systematic identification of hazards and implementation of risk reduction measures before deployment
• Safety-rated control systems and emergency stop functions must meet specific performance criteria to ensure reliable hazard mitigation

ANSI/RIA R15.06: U.S. Industrial Robot Standards

• The American adoption of ISO 10218—harmonizes U.S. requirements with international standards for consistent global safety practices
• Safeguarding requirements specify how to protect workers through physical barriers, presence-sensing devices, and safe operating procedures
• Installation and operation guidelines extend beyond robot design to cover the entire workcell lifecycle, including maintenance access

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Collaborative Robot Standards

Collaborative robots (cobots) require specialized standards because they intentionally share workspace with humans during operation. The safety philosophy shifts from separation to controlled interaction through speed limits, force limits, and continuous monitoring.

ISO/TS 15066: Collaborative Robot Safety

• Defines four collaborative operation modes—safety-rated monitored stop, hand guiding, speed and separation monitoring, and power and force limiting
• Biomechanical limits specify maximum allowable forces and pressures for different body regions, derived from pain threshold research
• Dynamic risk assessment is essential because hazard exposure changes constantly as humans move through the shared workspace

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Personal Care and Service Robot Standards

Personal care robots operate in unstructured environments with untrained users—a fundamentally different risk profile than industrial settings. Standards here emphasize user-centered design and account for vulnerable populations.

ISO 13482: Personal Care Robot Safety

• Covers three robot types—mobile servant robots, physical assistant robots, and person carrier robots, each with distinct hazard profiles
• Human-robot interaction risks receive special attention, including psychological factors like user trust, predictability, and comfort
• User-centered design requirements ensure robots remain safe even when operated by individuals without technical training or physical limitations

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Control System Safety Standards

These standards address how safety functions are implemented in hardware and software. They ensure that safety-related control systems perform reliably even when components fail.

ISO 13849: Safety-Related Control Systems

• Performance Levels (PL) from 'a' to 'e' quantify the reliability of safety functions, with PL e providing the highest risk reduction
• Safety categories define architectural requirements—how the system must be structured to achieve fault tolerance
• Diagnostic coverage requirements ensure that dangerous failures are detected before they can cause harm

IEC 61508: Functional Safety Framework

• Safety Integrity Levels (SIL) from 1 to 4 specify target failure rates for safety functions in electrical/electronic systems
• Safety lifecycle approach requires systematic processes from concept through decommissioning, not just design-phase analysis
• Provides the theoretical foundation that ISO 13849 and other machinery standards build upon for practical implementation

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Regulatory and Operational Requirements

Beyond design standards, these guidelines govern how robots are actually used in workplaces. They translate technical requirements into operational procedures and employer responsibilities.

OSHA Guidelines for Robotics Safety

• Legal enforcement authority in U.S. workplaces—OSHA can cite employers for robot-related hazards under the General Duty Clause
• Training requirements mandate that workers understand robot hazards, safeguarding systems, and emergency procedures before working near robots
• Inspection and maintenance protocols must be documented to demonstrate ongoing compliance with safety requirements

Risk Assessment and Hazard Analysis

• Systematic hazard identification examines all robot operations, including normal use, maintenance, teaching, and foreseeable misuse
• Risk estimation evaluates both severity of potential harm and probability of occurrence to prioritize mitigation efforts
• Hierarchy of controls guides response: eliminate hazards first, then substitute, engineer controls, administrative controls, and finally PPE

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Physical Safety Implementation

These represent the tangible safety measures that protect workers—the visible layer of the safety system that most people recognize.

Safety Guarding and Protective Measures

• Physical barriers including fences, enclosures, and fixed guards provide the most reliable protection by preventing access entirely
• Presence-sensing devices—light curtains, safety mats, laser scanners—detect intrusion and trigger protective stops
• Interlocks on access doors ensure robots cannot operate at hazardous speeds when guards are open or removed

Emergency Stop Systems

• Category 0 or Category 1 stops are required depending on application—immediate power removal vs. controlled deceleration before power removal
• Accessibility requirements mandate E-stops be within reach of all operator positions and clearly marked with standardized red/yellow coloring
• Hardwired circuits ensure E-stop functionality remains independent of software or network failures

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Quick Reference Table

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Self-Check Questions

1. Which two standards would you reference when designing a collaborative robot application, and how do they work together?

2. Compare ISO 13849's Performance Levels with IEC 61508's Safety Integrity Levels—what's the key difference in their intended application scope?

3. A personal care robot will assist elderly users in their homes. Why is ISO 13482 more appropriate than ISO 10218 for this application, and what unique risks does it address?

4. An FRQ describes a factory installing new welding robots and asks what safety documentation is required. Which standards and guidelines would you cite, and in what order of priority?

5. Explain why emergency stop systems alone are insufficient for robot safety—what other protective measures must work alongside them, and what principle does this illustrate?