Robot Safety Resources


REGULATIONS & STANDARDS

There are currently no specific OSHA standards for the robotics industry. This section highlights OSHA standards and documents related to robotics.

OSHA Standards

Section 5(a)(1) of OSHA Act – General Duty Clause

Subpart J – General Environmental Controls

  • 29 CFR 1910.147 – The control of hazardous energy (lockout/tagout)

Subpart O – Machinery and Machine Guarding

  • 29 CFR 1910.211 – Definitions
  • 29 CFR 1910.212 – General requirements for all machines

Depending on the material being processed, these standards are also applicable:

  • 29 CFR 1910.213 – Woodworking machinery requirements
  • 29 CFR 1910.215 – Abrasive wheel machinery
  • 29 CFR 1910.216 – Mills and calenders in the rubber and plastics industries.
  • 29 CFR 1910.217 – Mechanical power presses

Subpart S – Electrical

  • 29 CFR 1910.333 – Selection and use of work practices

OSHA Directives

Guidelines For Robotics Safety. STD 01-12-002 [PUB 8-1.3], (September 21, 1987). Provides guidelines to OSHA compliance officers, employers, and employees for the safe operation and use of robots and robotic systems.

OSHA Technical Manual (OTM). OSHA Directive TED 01-00-015 [TED 1-0.15A], (January 20, 1999).

Industrial Robots and Robot System Safety. Includes safety considerations necessary to operate the robot properly and use it automatically in conjunction with other peripheral equipment. This instruction applies to fixed industrial robots and robot systems only.

National Consensus Standards

American National Standards Institute (ANSI)

It provides safety requirements for industrial robot manufacture, remanufactures, and rebuild (Part 1); and robot system integration/installation (Part 2). R15.06 (ANSI/RIA R15.06-2012) is the U.S. National Adoption of the ISO 10218-1,2:2011.

  • B11.0-2015, Safety of Machinery – General Requirements and Risk Assessment.

Applies to new, existing, modified, or rebuilt power-driven machines, not portable by hand while working, used to shape and/or form metal or other materials by cutting, impact, pressure, electrical, or other processing techniques, or a combination of these processes. This can be a single machine, a machine tool, or a machine tool system(s), and may include industrial robot(s) and robot system(s). It also contains guidance on performing risk assessments.

  • B11.19-2010, Performance Criteria for Safeguarding.

Consolidates all of the design, installation, operation, and maintenance of Fixed Guards into a single standard. This standard specifies the material that safeguards (e.g. fixed guards, light curtains, interlocks, etc.) should be constructed out of, distance parameters based on the height of the guard and reach-over potential by employees, as well as the performance levels of the safeguarding technology and computer controls of the system.

  • B11.20-2017, Safety Requirements for Integrated Manufacturing Systems.

Specifies the safety requirements for the design, construction, set-up, operation, and maintenance (including installation, dismantling and transport) of integrated manufacturing systems, which may include industrial robot(s) and robot system(s).

International Organization for Standardization (ISO)

  • TC 299, Robotics.

Develops high quality standards for the safety of industrial robots and service robots to enable innovative robotic product to be brought onto the market. In addition, develops standards in fields like terminology, performance measurement and modularity.

  • ISO 10218-1: 2011, Robots for industrial environments – Safety requirements – Part 1: Robots.

Specifies requirements and guidelines for the inherent safe design, protective measures, and information for use of industrial robots. It describes basic hazards associated with robots, and provides requirements to eliminate or adequately reduce the risks associated with these hazards.

  • ISO 10218-2:2011, Robots for industrial environments – Safety requirements – Part 2: Robot systems and system integration.

Specifies requirements and guidelines for the safe integration of an industrial robot into a complete robot system, which includes end-effectors and other related equipment. This document describes basic hazards associated with robot systems, and provides requirements to eliminate or adequately reduce the risks associated with these hazards.

In the U.S., ISO 10218-1,2:2011 has been Nationally Adopted as the single U.S. standard ANSI/RIA R15.06-2012 (see above for details).

Note: ISO 10218 does not apply to non-industrial robots although the safety principles established in ISO 10218 may be utilized for these other robots. Examples of non-industrial robot applications include, but are not limited to: undersea, military and space robots; tele-operated manipulators; prosthetics and other aids for the physically impaired; micro-robots (displacement <1 mm); surgery or healthcare; and service or consumer products.

  • ISO/TS 15066:2016, Collaborative Robot Safety.

Provides important information about how to implement a collaborative robot system in a manner that maintains safety for the human operator. In the U.S., this ISO TS has been Nationally Adopted as TR 606 (see above).

  • ISO/TR 20218-1:2018, Safety Design for End-effectors.

Describes how an industrial robot system should handle and manage end-effectors (end-of-arm tooling or EOAT) to maintain human safety, in either a collaborative or non-collaborative industrial environment.

  • ISO/TR 20218-2:2017, Safety Design for Manual Load/ Unload Stations.

Describes how to design a Manual Load/ Unload Station (MLUS) that will be safe and effective for the human worker to use.

Canadian Standards Association (CSA)

  • Z434-14, Industrial Robots, and Robot Systems.

Applies to the manufacture, remanufacture, rebuild, installation, safeguarding, maintenance and repair, testing and start-up, and personnel training requirements for industrial robots and robot systems. This is the Canadian National Adoption of ISO 10218-1,2:2011.

American Welding Society (AWS)

  • 1M/D16.1

Specification for Robotic Arc Welding Safety. Identifies hazards involved in maintaining, operating, integrating, and setting up arc welding robot systems.

 

OVERVIEW OF ROBOT SAFETY

What is an Industrial Robot?

Industrial robots are programmable multifunctional mechanical devices designed to move material, parts, tools, or specialized devices through variable programmed motions to perform a variety of tasks. Robots are generally used to perform unsafe, hazardous, highly repetitive, and unpleasant tasks. They have many distinct functions such as material handling, assembly, arc welding, resistance welding, machine tool load and unload functions, painting, spraying, etc.

Studies indicate that many robot accidents occur during non-routine operating conditions, such as programming, maintenance, testing, setup, or adjustment. During many of these operations the worker may temporarily be within the robot’s working envelope where unintended operations could result in injuries.

An industrial robot system includes not only industrial robots but also any devices and/or sensors required for the robot to perform its tasks as well as sequencing or monitoring communication interfaces.

A robot cell is a complete system that includes the robot, controller, and other peripherals such as part positioners, safety devices, and barriers and other safeguards. An example of a typical industrial robot cell can be seen below.

An example of a typical industrial robot cell

 

Industrial robots are available commercially in a wide range of sizes, shapes, and configurations. They are designed and fabricated with distinctive design configurations and a different number of axes or degrees of freedom. These factors of a robot’s design influence its working envelope (the volume of working or reaching space). Diagrams of the different robot design configurations are shown below.

 

Robot arm design configurations

 

Robots can be classified according to multiple aspects and consideration (e.g. configuration, control system, path generation, etc.)

Collaborative Robots

A collaborative robot is a robot system specifically designed for direct cooperation with humans within a defined workspace. This is in contrast with other robots, designed to operate autonomously or with limited guidance, which is what most industrial robots were until the mid-2010’s. A typical industrial robot is a large and robust device that works on specified tasks, is surrounded by fencing or guarding, and require a lot of programming. Collaborative robots are compact, lightweight, and dexterous.

Due to the direct contact between humans and the robot, protective measures shall be provided to ensure the operator’s safety at all times. In accordance with consensus standards discussed below, the following requirements shall be fulfilled:

  • The integrator/installer shall conduct a risk assessment of the entire workspace and all collaborative tasks. (More information on risk assessments can be found in Section 6.1 of this program.
  • Safety precautions and protective devices shall meet minimum specifications outlined by the equipment manufacturer.
  • The safeguarding shall be designed to prevent or detect any person from advancing further into the safeguarded space beyond the collaborative workspace. Intrusion into the safeguarded space beyond the collaborative workspace shall cause the robot to stop and all hazards to cease.
  • The perimeter safeguarding shall prevent or detect any person from entering the noncollaborative portion of the safeguarded space.

To be able to be used with direct contact of humans, additional safety features are installed within the robot system. Some of these features include:

  • Integrated sensors to stop the robot’s movement due to external forces (e.g. hitting equipment or personnel);
  • Passive compliance by mechanical components, allowing a robot’s joint to submit should an external force be applied to it;
  • Automatic shutoff if the robot system detects an exceedance in voltage.

There are 4 types of collaborative robots.

  1. Safety-rated monitoring stop – This robot will stop when a human is within the collaborative workspace and resume when the human leaves the space.
  2. Speed and separation monitoring – This robot will maintain a pre-set speed and separation distance from the operator. The robot speed slows as the operator moves toward the robot.
  3. Power and force limiting – The robot is designed to limit power and force, it allows for incidental contact with the robot, as the robot is not operating at a speed or force that is harmful.
  4. Hand guiding – A human operator can teach, move, and stop the robot with his/her hands.

 

HOW TO IMPROVE ROBOT SAFETY

According to the Occupational Safety & Health Administration (OSHA), most accidents with robots occur during programming, maintenance, repair, setup and testing, all of which involve human interaction. To reduce accidents and improve robot safety, it is important to implement the following industrial robot safety tips:

  • Use boundary warning devices, barriers and interlocks around robot systems.
  • Provide annual robot safety training for employees working on the floor with robots.
  • Provide work cell operators with training geared toward their particular robot.
  • Create and implement a preventive maintenance program for robots and work cells;
  • Ensure operators read and understand robot system documentation, including that related to robot safety.
  • Allow only capable employees who know the safety requirements for working with a robot to operate robot systems.

Along with implementing industrial robot safety practices for a facility and its personnel, it is important to ensure the robotic work cell satisfies the following requirements:

  • The maximum reach of a robot should be marked on the floor with safety tape or paint.
  • A flashing warning device must be visible from any point around the work cell.
  • Safety curtains, fences or work cell equipment should be used as barriers around the cell to protect employees.
  • Emergency stop buttons should be located around the cell.

RISK ASSESSMENT

One item that is required according to the ANSI Standard ANSI/RIA R15.06-2012 and ANSI B11.0-2010 is that all facilities that utilize robots shall conduct a risk Assessment of the equipment. A risk assessment is a process in which one identifies hazards, analyzes or evaluates the risks associated with the hazards, and determines appropriate ways to eliminate or control the hazards. Risk assessment must now be completed when planning and integrating robot systems. The importance of evaluating each device’s risk is a major factor in risk assessment, as no two robot systems are alike.

Because a robot system is always integrated into a particular application, the integrator shall perform a risk assessment to determine the risk reduction measures required to adequately reduce the risks presented by the intended application of the robot. Particular attention should be paid to instances where safeguards are removed from individual machines.

The risk assessment enables the systematic analysis and evaluation of the risks associated with the robot system over its whole lifecycle (i.e. commissioning, set-up, production, maintenance, repair, decommissioning).

Risk assessment is followed, whenever necessary, by risk reduction. When this process is

repeated, it gives the iterative process for eliminating hazards as far as practicable and for

reducing risks by implementing protective measures. Risk assessment includes:

  • determination of the limits of the robot system;
  • hazard identification;
  • risk estimation;
  • risk evaluation.

A risk assessment should be conducted at each stage of the development process of a robot and robot system, as well as at any time that equipment within the robot system, the robot itself, control, or engineering changes occur. It is a good idea to conduct a risk assessment periodically to ensure that any procedures or safeguards put in place are functioning properly and providing adequate safety to all surrounding personnel and property.

TRAINING

 Extensive training should be provided for all employees who will be programming, operating, or maintaining robots. It could be beneficiary for even those employees who work in areas near robots and robot systems. The training should emphasize the safe work procedures and safe movement around robot systems as well as instruct employees in the methods of programming, starting up and stopping the robot. Newly trained employees may require close supervision until they adjust to the robot.

Specific aspects of any training program should include the following:

  • Operators should never be in the work envelope while the robot is operational.
  • Because programming must be done inside the work envelope while the robot is operational, programmers should operate the robot at a slow safe speed, and be made aware of all the possible pinch points where his body or extremities could be trapped.
  • Refresher training should be conducted periodically for experienced robot programmers and operators to ensure they are regularly familiarized with the safety standards and limitations within the robot systems.
  • During programming, the robot should be stopped at each intermediate step and all possible pinch points should be identified and eliminated if possible.

All operators and maintenance personnel should be instructed that “Just because robot is stopped, don’t assume that it will remain stopped”, and “If a robot is repeating a motion, don’t assume that it will continue to repeat only that motion.” This will remind employees that robots operate within a specified set of guidelines, however, errors can occur and robots are heavy pieces of industrial machinery. Special safety precautions should be considered when working with or around robots.