Orin and Group:
So, you have an AC powered device that delivers energy in some form to the patient and also has a connection to said patient, even if isolated. Sounds like a type BF Applied Part classification. The CISPR Class A implies use in hospitals only. All the EMC tests you listed look appropriate to me. As for the 601-1 Particulars, the test lab may be just using certain applicable parts of the -2-26 and -2-40 Particular Standards to evaluate safety concerns (leakage currents, dielectric levels, etc.) not addressed in the base Standard, due to the similarity of this product and full-blown EEGs and/or EMGs. This was common practice at UL a few years ago and I doubt the lab thinks that the user will try to stimulate their own head – but stranger things have happened (nurse plugs infant EKG lead into mains outlet…). It might be interesting if you’d included the first test lab’s list of Standards, the one that prompted the second opinion and the resulting list in your post. Or were they rather similar? Actually, the list seems to be missing -2-10: Medical electrical equipment - Part 2-10: Particular requirements for the safety of nerve and muscle stimulators Probably also count on a software (60601-1-4) evaluation if S/W controls the delivered energy and could cause a hazard (RF burns, etc.). OOO – Own Opinions Only, neither my current nor any previous employers’ Best, Bryce p.s. – Wanna see a test list that will knock your socks off? Try testing for an of hospital, direct cardiac-connected, rechargeable battery powered, 100-250 Vac mains powered and DC automotive powered, life support device that users routinely take in airplanes (and medivac helicopters)!?! From: [email protected] [mailto:[email protected]] Sent: Monday, November 16, 2009 12:55 PM To: [email protected] Subject: [PSES] How much is enough? One of the things I watch out for is over-testing of new products, because of the cost and time implications. Recently I was asked to comment on the test requirements for a piece of medical gear. Nothing in the technology is new, similar devices have FDA approval, so the goal is to determine a minimum set of tests that will likewise achieve approval. The problem is that a local test lab supplied a quote that basically amounted to saying "Medical device? Kaching!$!", and listed seemingly every test that might possibly apply, with a price to match. Then another test lab was asked if a more modest approach was possible, and they came up with the following: IEC 60601-1 (General Requirements for Safety) Including all applicable clauses IEC 60601 -1-2 (Collateral Standard: Electromagnetic Compatibility) Including – a) CISPR 11 Class A Group 2 (Conducted and Radiated) b) IEC 61000-3-2 Power Line Harmonics c) IEC 61000-3-3 Power Line Flicker d) IEC 61000-4-2 ESD e) IEC 61000-4-3 Radiated Immunity f) IEC 61000-4- 4 EFT g) IEC 61000-4-5 Surge h) IEC 61000-4-6 Conducted Immunity i) IEC 61000-4-8 Magnetic Immunity j) IEC 61000-4-11 Power Line Dips and Brownouts IEC 60601-2-26 – (Particular Requirements for Safety of Electroencephalographs) Scope of use limited by application of device. IEC 60601-2-40 – (Particular Req. for Safety of Electromyographs and Evoked Response Equipment). Scope of use limited by application of device. This particular equipment uses a pulsed electric field for nerve stimulation of a foot or hand. Operation is contactless, so the patient is fully insulated from the therapy circuitry. To monitor the patient there is a 3 wire EMG sensor that is fully optically isolated and passes hipot and leakage without any trouble. Power draw is under 150W via a standard IEC power cord plugged into a standard safety grounded receptacle. There is a membrane keyboard and VF display for control. All of this is contained in a single box, the EMG leads and power cord being the only cables. Comparing that against the test list, I question, for instance, the inclusion of EEG requirements. One might suppose that the box could be misused by someone placing their forehead against the therapy surface to see if it feels good, but the operation manual proscribes things like that. The basic question here is what can be dispensed with, and what seems to have been left out. I sense that community opinion ranges from a totally barebones approach to fully developed CYA paranoia (in which case the hypothesized off-label experiment might prove beneficial). What think ye? Orin Laney - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]> - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher <[email protected]> David Heald <[email protected]>
