Machine safety: Incorporating functional safety, part 2

When considering “functional safety,” look at what differs compared to other safety initiatives, consider U.S. versus international standards, examine conformance responsibilities, and think about what changes are needed, if any, as a manufacturer. Part 2 of 4 looks at U.S. vs. international safety.

By JB Titus March 22, 2013

When considering “functional safety,” look at what differs compared to other safety initiatives, consider U.S. versus international standards, examine conformance responsibilities, and think about what changes are needed, if any, as a manufacturer.

1. What is so different about “functional safety”? (Part 1)

2. Are U.S. domestic standards adopting functional safety requirements from the international standards?

3. Do the international standards place primary conformance responsibility on manufacturers like with OSHA?

4. Do we have to change our machine safety program as a manufacturer in order to meet the compliance requirements?

Let’s take a look at these four questions addressing the second question in Part 2.

Definition from IEC 61508-1 – Functional safety is “part of the overall safety relating to the equipment under control and the equipment under control’s control system which depends on the correct functioning of the Electrical/Electronic/Programmable Electronic safety-related systems, other technology safety-related systems and external risk reduction facilities”.

Are U.S. domestic standards adopting functional safety requirements from the international standards?

Who has an answer or supporting comment about this question? I can say from my perspective that several domestic standards bodies are beginning to roll some of the new requirements into their standard during scheduled update cycles. International standards, like ISO 13849-1: 2006 Safety of machinery —Safety-related parts of control systems, are clear to state that their intended audience is designers.

So my advice is that you should take careful notice of your particular standards for your business and types of machines to see if and how your particular standard might be impacted. For example, as an OEM or systems integrator you will most likely see these changes because of your machine control design activities within your business. On the other hand if you are an end user with no control system design engagement just how these changes impact your end user requirements is still unclear in my perspective.

You may not design circuits for your machines and you may not have designers within your business. Even though you may not be engaged in the design of machine control systems don’t you still need to be aware that the requirements will focus more strongly on the functions that are necessary to reduce each individual risk, and what performance is required for each function, rather than simply relying on particular components?

Have you found difficulty understanding any of these issues?  Add your comments or thoughts to the discussion by submitting your ideas, experiences, and challenges in the comments section below.

Related articles:

Inside Machines: Does adopting ISO 13849-1:2006 change the U.S. model for compliance and enforcement?

Machine Safety – does OSHA reference consensus standards for compliance?

Machine Safety: Is OSHA okay with my ‘acceptable’ risk mitigation?

Contact: https://www.jbtitus.com for “Solutions for Machine Safety”.