35.3. National and International Safety Standards

Key requirements include:

• Emergency stop buttons
• Protective enclosures and safety-rated monitored stops
• Guidelines for installation and maintenance

ISO 10218 outlines essential safety requirements for industrial robots. This includes the implementation of emergency stop buttons that allow operators to halt machines immediately during emergencies. Protective enclosures are necessary to shield humans from moving parts and ensure safety-rated monitored stops where robots automatically stop if safety parameters are breached. The standard also specifies guidelines for proper installation and maintenance, focusing on ensuring that robots operate safely throughout their lifecycle.

Imagine an industrial robot assembling car parts on a production line. Without an emergency stop button, a worker could be seriously injured if they accidentally come too close to the robot's moving arms. The protective enclosure acts like a safety fence, preventing workers from entering a dangerous area while still allowing them to observe the robot's operation safely.

Applicable to robots working alongside humans:

• Maximum allowable contact force
• Speed and separation monitoring
• Power and force limiting modes

ISO/TS 15066 focuses on the safety of collaborative robots that work alongside human operators. This standard specifies a maximum allowable contact force, which is the limit on how much force a robot can exert during physical interactions with human workers. Additionally, it emphasizes the importance of monitoring the robot's speed and the distance between the robot and human workers to prevent accidents. Power and force limiting modes are features that ensure the robot operates within safe parameters, reducing potential risks of injury.

Consider a factory where a collaborative robot and a human worker work side by side on an assembly line, passing parts to each other. If the robot accidentally bumps into the worker, it must only apply a light, safe force to avoid injury — similar to how a gentle tap on the shoulder is safe, but a hard shove could be harmful.

Covers the safety lifecycle:

• Risk analysis
• Safety integrity levels (SIL)
• Verification and validation

IEC 61508 outlines the functional safety requirements for systems that include electrical, electronic, and programmable elements. This standard is crucial in defining a safety lifecycle that includes conducting risk analysis to identify potential hazards. It establishes Safety Integrity Levels (SIL) that classify the required safety measures based on the level of risk associated with system failures. The verification and validation processes mentioned are essential to ensure that safety measures are effective and that systems function correctly under expected conditions.

Think of IEC 61508 as a safety blueprint for an airplane. Before it takes off, engineers conduct thorough risk analyses (like evaluating what could go wrong), classify each component's reliability (like the redundancy of engines), and regularly validate systems through rigorous testing to ensure safe flights.

Emphasizes:

• Safeguarding methods (light curtains, area scanners)
• System design validation
• Operator training and lockout/tagout procedures

The ANSI/RIA R15.06 standard focuses on the safety of industrial robots in North America. It emphasizes safeguarding methods, such as light curtains and area scanners, which detect the presence of workers in robot workspaces and prevent unintended operations. System design validation is important to ensure that the robotic systems have been assessed for safety before being put into operation. Operator training is critical for safe interaction with robots, and lockout/tagout procedures ensure that equipment is properly shut down and locked before being serviced.

Consider a factory equipped with light curtains that act like invisible walls around the robot's workspace. If a worker approaches the robot too closely, the light curtain senses their presence and immediately halts the robot's operations. This is a vital safety feature that helps prevent accidents, akin to a crossing guard stopping traffic when students are going to school.

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