Medical Electrical Equipment & UL Approval - Interpreting the Life-Cycle Diagram

[Dave-h]

I was wondering if anyone had any experience with electrically powered medical equipment and gaining UL approval.

The safety aspects are covered by the various sections of 60601. This particular tool, has some control logic connected to the trigger that controls the operation of the tool.

Because the tool now incorporates sofware, UL require us to ensure that this element complies with 60601-1-4.

If anyone is familiar with this, how did you interpret the life-cycle diagram, so that you could produce a plan that meets their requirements?


p.s. I'm sorry if this message is "off-topic" because it is not strictly 13485.

Many thanks,

[Al Rosen]

Originally Posted by Dave-h

I was wondering if anyone had any experience with electrically powered medical equipment and gaining UL approval.

The safety aspects are covered by the various sections of 60601. This particular tool, has some control logic connected to the trigger that controls the operation of the tool.

Because the tool now incorporates sofware, UL require us to ensure that this element complies with 60601-1-4.

If anyone is familiar with this, how did you interpret the life-cycle diagram, so that you could produce a plan that meets their requirements?


p.s. I'm sorry if this message is "off-topic" because it is not strictly 13485.

Many thanks,

If you are refering to the Development Life-Cycle, you may find the attached helpful. There are references to FDA type documents like, 510K (Similar to CE STED) And Device Master Record (Similar to CE Technical File) but otherwise I think it conveys the idea.

[Dave-h]

Thanks Al,

That certainly looks that it will be useful.

Part of my problem is interpreting a standard that was probably created with complex life support systems in mind, as opposed to our relatively simple product.

Thanks again for yoir help.


Dave

[wrodnigg]

Hello Dave-h, welcome at the cove

Maybe this document helps you a little bit with UL...

To the 60601-1-4 thing:

The Development Livecycle in 60601-1-4 is similar to the SDLC for Computerized Systems (just ask Google for "SDLC" and you will find plenty of information).

The Lifecycle Model (V-Model) can be read as follows:

On the left branch, you have specifications going downwards more and more into detail. Beginning with User Requirement Specifications (URS), detailed into Functional Specifications (FS) needed to meet the URS [here they are divided into FS of subsystems) and Design Specs (DS) of components which are needed to implement the functions of the FS.

In Phase 2 there is also the Risk Assessment (see ISO 14971 for details).

At the bottom of th "V" there is the system build.

Then you go up the verification branch, starting with module tests and component tests. A verification plan shows the relation between the tests an the specifications of the design specs.

Next is the functional testing against the subsystem-FS (guided by a verification plan).

Then you have the integration and system verification against the functional specs.

Finally there is the system validation to test if the system meets the URS.

So you have tests for all kinds of specifications plus tests for risk aspects from the risk assessment. The horizontal curves indicate verification- and validation-plans (documents which include test definitions and acceptance criteria).

This SDLC is also described in the GAMP4-Guide.

If there are any further question, just ask...

And if you want just a simple way, look at the V-Model in the GAMP4-Presentation. It is quite similar to the Lifecycle of 60601-1-4

[Dave-h]

Thanks Wrodnigg,

that all looks very useful.


Dave

[wrodnigg]

Additional note:

60601-1 is currently under revision (62A/449/CDV).
Some aspects of 60601-1-4 are expected to be included in the new 60601-1 (PEMS - Programmable Electrical Medical Systems).

And maybe you are interested in a draft version of IEC 62304 (62A/446/CD) "Medical device software - Software lifecycle processes"

[Dave-h]

Thanks for the reply.

The draft of IEC 62304 looks interesting. I wonder what their plans are for the standard, as it seems to have the feel of a management systems type standard, and it uses the term "Shall" rather liberally! From a small company point of view, it is worryingly prescriptive. Certainly one to watch out for.


Dave