Regulatory Open Forum

Hi all,

Recently our NRTL certification service have informed us that in order to approve further changes to our product they will have to assess a much wider scope of the IEC 60601 family than they currently do. My understanding of NRTL was that it is primarily OSHA's scheme for ensuring electrical safety of the operator, with some additional constructional safety aspects. Now the certification service is requiring coverage of other areas more within the purview of FDA (they have requested all specific and collateral standards other than EMC and Biocompatibility).

For context. We have previously had IEC 60601-1, the particular standard, and IEC 60601-11 assessed, excluding clauses relating to alarms, functional safety, biocompatibility, and PEMS. We have previously heard that the service's Canadian branch started requiring coverage of all collateral standards other than EMC - but functional safety was not added as a requirement at that stage.

Does anyone else have experience or a greater understanding of this situation?

Hi Anon,

The comment you said: "My understanding of NRTL was that it is primarily OSHA's scheme for ensuring electrical safety of the operator, with some additional constructional safety aspects."  Is not a correct understanding of the NRTL program.  To understand the OSHA program go to OSHA NRTL mark https://www.osha.gov/nationally-recognized-testing-laboratory-program/frequently-asked-questions#manufacturers_suppliers.
One of the important FAQs in this section is below

• OSHA's authority is limited to employers; therefore, OSHA does not require manufacturers or suppliers, as applicable, to have the products they manufacture or supply certified by an NRTL. That said, it would be in the interest of manufacturers or suppliers, as applicable, to have products requiring approval under OSHA standards to be NRTL-certified, as many, if not all, of their customers are most likely employers that must follow applicable OSHA standards requiring approval of products and equipment.

Reading between the lines and doing some interpretation: Most OSHA NRTL test houses also have other test programs that can issue certificates and safety marks, such as the CB scheme, the test lab can issue their own mark, etc..  Realize that an OSHA NRTL certification does end up with a set of test reports, a safety mark (assuming the testing and constructions, labeling, etc are all acceptable and meet the applicable standards) and factory inspections are part of the OSHA program with the end result of a NRTL approval.  The testing isn't specifically related to just ANSI/AAMI ES 60601-1 (that is what OSHA NRTL program approves test labs for as the OSHA program under the medial electrical requirements) but all applicable collaterals (IEC 60601-1-XX usually EMC is excluded) and particular standards (IEC 60601-2-XX or IEC/ISO 80601-2-XX) would apply.  But that is what OSHA approves is to the ANSI/AAMI ES 60601-1 standard which is basically IEC 60601-1 with a few pages of national deviations.

So, it is normal for most reputable and good test houses to test to IEC 60601-1, all applicable collateral and particualr standards and also you have usability is reviewed per IEC 60601-1-6 as it is a bridge to IEC 62366-1 and IEC 62304 for software lifecycle processes. 

Several things I have found that clients don't do is 1) first determine the applicable standards, laws, directives, guidances, etc. that apply to your device based on markets planning to get into (& not just short term but also long term), 2) identify the applicable Essential Performance (could be more than one) for your device (FDA expects you to have EP for every device (very few exceptions if any exist) and good luck fighting that) 3) design the product with all these requirements in mind so able to pass the tests easier, 4) set-up a test plan for both safety and EMC, 5) do applicable pretesting (primarily EMC issues need this more) so you set your self up for successful testing and results. Then move onto testing there are other steps but these are some of the items a lakc of pre-planning will make things harder for you.

Functional Safety is not a requirement of the IEC 60601-1 series of standards and I would argue shouldn't be brought up in the context of IEC 60601-1 series of standards.  Functional safety is based on IEC 60513 and there is a very different view on risk management than from a medical perspective in that standard and they don't consider ISO 14971 for medical device risk management.    I am on the project & writing team (IEC TC62 / SC62A / PT 62A-1) hat has been developing a guidance-type document under the IEC for Essential Performance and Single Fault Safety to expand on the Interpretation Sheet 1 for Essential Performance and SIngle Fault Condition. We hope this guidance document as an IEC TS (Technical Specification) not as a standard will come out late this year (not a guarantee).  Attached is the ISH1 and is available for free on the IEC website as a public document - even though you need to know how to navigate the site (pretty tricky at times :)). 

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Leonard (Leo) Eisner, P.E.
The "IEC 60601 Guy"
Principal Consultant, Eisner Safety Consultants
Mobile: (503) 709-8328
Email: Leo@EisnerSafety.com
Website: www.EisnerSafety.com
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Attachment(s)

ISH 1 IEC 60601-1 ed 3.1 EP + SFC.pdf   104 KB 1 version

Thank you for your response Leonard. Reading through I realise that my use of the phrase "Functional Safety" was incorrectly applied; what I meant to describe was actually Essential Performance and related protective systems.

Browsing OSHA's listing of specific references for electrical devices I can see electrical and mechanical safety, along with other concerns that align with their remit being workplace health and safety. What I don't see is coverage of clinical function / therapy / Essential Performance - other than in the context of device failure to function. For complex medical devices, including EP protective systems could be a large volume of testing with very specific equipment/set-ups, already done and accepted by the FDA, adding substantial burden and complication to the NRTL service provider's activities. Am I still missing something that explains OSHA's concern with clinical function?

Additionally, I have struggled to understand why EMC is excluded from NRTL when the EMI component is very relevant to devices in the workplace environment. Especially if the scope is otherwise broad enough that Essential Performance of clinical function is included.