Search the Elsmar Cove!
**Search ALL of** with DuckDuckGo Especially for content not in the forum
Such as files in the Cove "Members" Directory

IEC 60601-1 subclause 5.1 - Adequate evaluation in lieu of testing

I'm curious if anyone here has any experience utilizing subclause 5.1 when obtaining IEC 60601-1 certification from a test lab. For those unfamiliar, the relevant section of sublcause 5.1 here reads:
A test need not be performed if analysis shows that the condition being tested has been adequately evaluated by other tests or methods.
We are looking to swap out a critical component in our device. Both the old and new critical components are themselves IEC 60601-1 certified. We went through those 60601-1 test lab reports to pull relevant test data out and make a technical comparison of behavioral difference that we feel--per 5.1--adequately demonstrates the change wouldn't result in us failing to continue to meet the specs called out in 60601-1 for the whole system. What I'm trying to get from the test lab is an explanation of why our evaluation was not adequate, but can't seem to get a straight answer. Is there something I'm missing?

I know that in 60601-1 test reports for certified medical device components, it commonly explicitly states that certain sections of 60601-1 need to be evaluated on the full system instead of just that component, but would an adequate evaluation per 5.1 meet that requirement? Ultimately I just want to understand how everything here ties together, or why our evaluation is not adequate.

Not expecting in-depth technical analysis here (obviously, since I'm not providing specifics), just want to know if anyone here has experience with utilizing 5.1.
I worked for a test house before moving on to a notified body to audit medical device manufacturers. In the handful of cases clause 5.1 was leveraged successfully, most pertained to temperature tests of low power (<15W) components downstream of the 60601-1 ed 3.0 (or 3.1) Switch Mode Power Supply. Typically, it is quicker to simply retest (leakage, worst-case temp test for that component from the previous evaluation, the loading tests for suspended masses, and/or dielectric) than to get an exception via 5.1 signed off by reviewers, perhaps even chief engineer in the case of mechanical support systems or MAINS connected components.

All that said, it depends on the component, accessibility to the user/patient, and risk analysis. By definition, critical components are necessary for either safety or essential performance and are therefore subject to more scrutiny. If the new component performs differently than the original component, then the device may likewise perform in a manner that is less safe or that does not meet essential performance requirements. Perhaps the new component has an unidentified failure mode that the current risk management file does not account for.

If you have test reports from an accredited lab of the component in similar or worse-case scenarios, the test house may accept those in lieu of performing a new test. Most labs I have worked with adhere to some form of common sense engineering, even the more risk-averse ones.
I'm curious about the genesis of the question. Are you seeking to save on certification costs or reduce time to market?
Well, you're right about it being quicker to simply re-test as opposed to work a 5.1 exception. Luckily I'm in a position where we have a few months until we'll be forced to switch to the new component.
Top Bottom