Automation, Safety, and Robotic Systems

The creative pace of solution seekers always seems to move faster than regulations and controls. In some ways that can be good, and in some ways, it can create unforeseen hazards when those solutions, such as robotics and automation, are introduced into a workplace.

What You Need to Know About the Current Automation Guidelines

It is no secret that automation has moved forward and that the pace of that expansion has significantly outpaced enforceable safety regulations. The current guidelines on the OSHA website were written in 1987, and the previous technical chapter was written in the early 2000s. In September of 2021, OSHA issued a new technical manual chapter titled, Industrial Robot Systems and Industrial Robot System Safety.

While a technical manual is not a regulation, it is the material OSHA uses to educate their duty officers and the basis from which an OSHA duty officer might choose to enforce 1910.147 (the Control of Hazardous Energy), Subpart O (Machine Guarding), or even the general duty clause to cite an employer.

It is important to make mention of the fact that 1910.147 and Subpart O are consistently in the top 10 most cited standards year after year, and in some industries, they frequent the top two or three. More importantly, the chapter helps employers and safety professionals develop systems to protect employees from a unique set of hazards. It breaks down some of the individual elements of moving a robotic system from manufacturing to actual integration, set up, and use in the workplace.

Putting Robotics into Practice

When moving to use of robotic automation, an essential consideration is how a robotic workstation can be integrated into the specific workplace and task it is meant for. Some companies choose to have a third party integrate and some may decide to use their own internal expertise.

Using a third party transfers some level of risk, providing the contract is written correctly with favorable insurance language. It is also possible for the employer to require the third party to conduct job hazard analysis outlines associated with the different jobs that will be performed in that specific workplace, with or around the robotic system. This may include operators, programmers (teachers), maintenance, cleaning, or others.

Each job task may require a different control mode, entail different hazards, and have different protections and sensors dedicated to the mode the robot must be in during specific tasks. They may also have different rules and requirements which apply to each specific task. The complicated nature of integration makes planning and careful detailed work specific to each job and task essential whether planning is conducted in house or with the assistance of a third party.

What You Need to Know About Integrating Outside Guards and Safety Systems

Part of the work and planning done during integration may also include choosing and installing barrier guards, interlocks, light curtains, or other sensors that do not always "come with" the robot but which must be integrated into the control system, and which are unique to that specific application and set up. Integration is made even more important by the fact that the safety device and control scheme decided on during integration is what the employer will rely on to protect their employees over time.

Whether collaborative (direct interaction with humans) or non-collaborative (no direct interaction with humans) robots are utilized determines what type of sensors, guarding, and programming will be combined to protect employees. Collaborative robot set ups will rely more on proximity sensors, speed controls, and programming to ensure employee safety. This does add to the complexity of the integration and programming and may increase the incentive to utilize a third party with extensive experience integrating collaborative robots and to seek favorable insurance terms whilst securing their services.

The differences in these two types of robots have resulted in two different ANSI standards being written. ANSI/RIA R15.06-2012 applies to non-collaborative robots and safety measures while RIA TR R15.606-2016 applies to collaborative robots.

How Employers Should Handle Robotics

Over time, guarding schemes, control systems, sensor type and position, end effectors (the robots implement for touching and working on the product) or other installer or manufacturer determined elements may need to change. As you consider whether to perform these changes on your own or tap the manufacturer and or installer to make those changes, it may help to consider some of the topics outlined in our previous blog on guarding and liability. An employer could take on manufacturer liability or nullify contractual protections if changes are made to the original manufacturer, or installer design, or set up.

For some functions and entry into the protected zone, hazardous energy controls (LOTO) must be utilized. In some cases, you can rely on equivalent protections, depending on several different factors including whether the entry meets all exceptions from 1910.147. Keeping in mind that the proper mode must be selected on the control panel for different protective mechanisms to function, you can see how it would be easy for an employee to enter a protected zone in the wrong mode and become injured. You must identify and control all these types of potential system hazards during implementation.

One scenario that might help explain why such careful planning is warranted is the following. Operators are not normally also programmers and so should not use teach pendants and teach modes. Teach mode selector knobs or controls are not locked out on most control panels that operators have access to.

If an operator is utilizing a non-collaborative robotic arm in the automatic mode and proper interlocked barrier guards are in place, then when the outside gate is opened the arm should stop immediately or come to a stop in just a few seconds. If the mode is changed to teach mode and the operator accesses the same restricted zone, it is possible for the robot to move and pin them.

Potentially, the only difference would be the position of the mode selector knob or controls effectively bypassing several protective safety sensors.

Final Thoughts on Robotic Automation

Feel free to contact your Woodruff Sawyer account team with questions around this and other safety and insurance matters.