Does anyone know of a resource that could tell me which devices (ie., silicone rubber coated ortho instruments) are required to meet USP Class 6 or other biocompatibility requirements?

Does anyone know of a resource that could tell me which devices (ie., silicone rubber coated ortho instruments) are required to meet USP Class 6 or other biocompatibility requirements?Although I can't claim to be an expert in this area but, I believe that ISO 10993 is being used instead of the USP for medical device biocompatibility testing. The tests that are required depend upon the length and type of contact. Look at FDA Blue Book Memo G95-1 (http://www.fda.gov/cdrh/g951.html). There is also a discussion on a similar topic in the thread, Biocompatibility - USP Class VI vs. ISO 10933 (http://elsmar.com/Forums/showthread.php?t=16152).

Although I can't claim to be an expert in this area but, I believe that ISO 10993 is being used instead of the USP for medical device biocompatibility testing. The tests that are required depend upon the length and type of contact. Look at FDA Blue Book Memo G95-1 (http://www.fda.gov/cdrh/g951.html). There is also a discussion on a similar topic in the thread, Biocompatibility - USP Class VI vs. ISO 10933 (http://elsmar.com/Forums/showthread.php?t=16152).
Thanks to Al's help and quite a bit of research and discussions with a Biocompatibility Lab (we use NAmSA) I've gained quite a lot of insight into this subject. I'm certainly not an expert either, but may be able to point you to some additional information if you're still looking.

We are a manufacturer of hearing diagnostic and screening products. We use an electrode that it put on the skin of the patient. The outer casing material of the elctrode is biocompatible. Should the wire used also be biocompatible, as it may touch the skin at some time? Where can I find the guidance document?

I have searched the forums for an answer to my question regarding biocompatibility. I have also looked in the Blue Book Memorandum #G95-1 but I could not find the proper guidance. I hope that somebody in the forum can help me in determining the FDA requirement.

Thanks

Amjad Rana

We are a manufacturer of hearing diagnostic and screening products. We use an electrode that it put on the skin of the patient. The outer casing material of the elctrode is biocompatible. Should the wire used also be biocompatible, as it may touch the skin at some time? Where can I find the guidance document?

I have searched the forums for an answer to my question regarding biocompatibility. I have also looked in the Blue Book Memorandum #G95-1 but I could not find the proper guidance. I hope that somebody in the forum can help me in determining the FDA requirement.

Thanks

Amjad Rana

From what you've said above, I assume by "wire" you mean the insulation on the electrode, correct? If so, I would then also assume that this would be in the ISO-10993 category of "Surface Device", "Skin Contact" and "Limited Exposure" if used for "hearing diagnostics". I would expect that you would then need to show compatibility of the insulation per the ISO 10993 Biocompatibility Test Matrix for this category.

I would recommend consulting with the test lab that provided results for the casing material of the electrode. They "do this every day" and should be able to provide useful guidance. Erring on the conservative side though, I would expect that the insulation material would have to meet those requirements.

-Steve

Dear Steve,

Thank you for your reply. No, I do not mean the insulation on the electrode. Our electrode is connected to the medical device through thin wires. We use an expoxy resin for the encapsulation of the PCB that is enclosed within the electrode. About one cm of the wires coming out of the elctrode are coated with the resin as part of the process. Would the thin wires and the epoxy resin also need to be biocompatible. These may come in touch with the skin of the patient being tested occasionally.

I hope that I am making myself clear.

Thank you for your input and assistance.

Amjad Rana

Dear Steve,

Thank you for your reply. No, I do not mean the insulation on the electrode. Our electrode is connected to the medical device through thin wires. We use an expoxy resin for the encapsulation of the PCB that is enclosed within the electrode. About one cm of the wires coming out of the elctrode are coated with the resin as part of the process. Would the thin wires and the epoxy resin also need to be biocompatible. These may come in touch with the skin of the patient being tested occasionally.

I hope that I am making myself clear.

Thank you for your input and assistance.

Amjad Rana
Perfectly clear! I by no means consider myself and expert in this subject, and the ISO and/or FDA documents are not crystal clear either. The only reference I've seen for contact duration are "<24-hr" listed as "Limited". Since your wires/epoxy definitely fall into this category since there skin contact potential is "incidental contact", the conservative approach would be to perform the testing.

I would again reiterate my original advice to check with your test house. I won't mention the lab we use (probably wouldn't be appropriate - but I can send you a private E-Mail if you like), but they have not "required" us to perform testing that would be unnecessary. In other words, I completely trust their advice when it comes to "which testing do we need?".

If you want the info on our lab, just send me an E-Mail. I'll keep an eye on my "private message" counter, or you can just E-mail me direct from the Cove.

-Steve