After some more work I learned that the issue is not specific to CPAP machines, but to equipment in an oxygen rich environment.
The requirement is in IEC 60601-1 subclause 11.2.2.1 b) 3) which deals with oxygen rich environments. A compartment that can cause a spark must be separated from another compartment with an oxygen risk environment by sealing. The subclause requires a risk assessment to determine the appropriate maintenance intervals of the seals.
The subclause has an asterisk. The associated explanatory section includes a method to calculate the time interval for checking the seals. This is the formula I was looking for. The original question asked if the formula is the correct method to calculate the frequency of occurrence of two independent events (a leak and a spark).
Original Message:
Sent: 05-Sep-2017 07:26
From: Dan O'Leary
Subject: IEC 60601 series v. ISO 80601 series
Thank you for the detailed response. I'd like to explain the path I followed, since it didn't lead me to the right place. This may also be of interest to others who need to navigate the system.
The original question came to me about "IEC 60601-2 sub clause 11.2.2.1 b) 3)". The section contains a formula for calculating the inspection time for CPAP masks as a function of the probability of an oxygen leak and the probability of an electrical spark. This is of interest to me because it should be analyzed as a hazard in the ISO 14971:2007 risk management file.
However, the citation is not correct, since it doesn't include the full reference in the form IEC 60601-2-X. My first question was to find the right standard. I went to the IEC website, http://www.iec.ch. In the search box I entered CPAP. I got back a table that lists ISO 80601-2-12:2011. I now recognize that the fine print says it doesn't apply to CPAP machines, but I missed that on the first reading. I thought I had the correct standard. The search engine gave me a standard that didn't apply, but not the standard that does.
I went to the ISO web site and searched for 80601-2-12. I learned from that page that the IEC standard is replaced by an ISO standard which is under review and due for replacement.
Believing I had the correct standard, I though the IECEE test report form might be interesting, since it might provide insight into checking conformance. This is important in risk management because the use of certain standards can significantly reduce the level of effort. If there were acceptability criteria, this standard might fit the criteria. Since this is now an ISO standard, I was curious if there were a TRF.
I went to the IECEE website, www.iecee.org, and entered 60601-2-12 in the search box. In the list of items returned it gave me IEC60601_2_12D, which applies to IEC 60601-2-12:2001.
This morning, I entered 80601-2-12 and found ISO80601_2_12B.
Between this process and your clarifications, I learned a lot. It is a good day. Thank you.
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Dan O'Leary
Swanzey NH
United States
Original Message:
Sent: 04-Sep-2017 02:08
From: Leonard Eisner
Subject: IEC 60601 series v. ISO 80601 series
Hi Dan,
An 80601-2-XX standard just means that it was jointly developed by ISO and IEC. Either of the organizations could be the lead and usually the standard number will include that it is IEC (if they were the lead on the project to develop the standard) or ISO (if they were the lead on the project to develop the standard).
There is no plan to switch IEC to ISO standards in the 80601-2-XX part of the IEC 60601 series of standards.
Note to find the most recent TRFs (test report forms) you need to go the CB Scheme TRF website and review the MED TRFs (Search box where the TRF list is not the top right search box). You will find more current info on TRFs on the CB Scheme TRF part of their website. The IEC site may be a bit behind, I am not sure if they are on the same db or not. They are part of the same organization. CB Scheme is under IECEE which is associated with IEC.
FYI the IEC and ISO 80601-2-12 TRF if you check the CB Scheme TRF website is the same document. I don't know where you found a version D of it. It is at revision level B for the 2011 standard. TRFs are only written when there is a need and a specific test lab that is part of the CB Scheme would be the one to write that specific TRF.
To understand more about this series of standards and get an update on standards that are updating in the 60601 series and related support standards please see the below links for a webinar I gave a couple weeks ago on this topic. The recording and slide links are below.
Webinar recording
Slide deck
Please feel free to pass this information onto others but please let them know I was the presenter in association with Medical Device Academy which I will be presenting at a 510(k) 2 day workshop in early October on section 17 of the 510(k) process for Electrical Safety & EMC.
The standard you mention ISO or IEC 80601-2-12 is for critical care ventilators not CPAPs. See below for the Abstract from the standard which is shown on the IEC website where they sell standards. See the bolded, italicized, Underlined text for the exclusion of CPAPs & similar devices.
The CPAP Standard is titled "...sleep apnoea breathing therapy equipment" and is under ISO 80601-2-70 issued in 2015. It's scope is copied below the 80601-2-12 standard abstract I got from the IEC.ch website.
I hope that answers all your questions.
All the best,
Abstract of IEC 80601-2-12:
"ISO 80601-2-12:2011 applies to the basic safety and essential performance of a ventilator in combination with its accessories, hereafter referred to as me equipment: - intended to be attended by a professional operator for those patients who are dependent on mechanical ventilation; and - intended for use in critical care environments in a professional healthcare facility or intended for use in transport within a professional healthcare facility. ISO 80601-2-12:2011 is also applicable to those accessories intended by their manufacturer to be connected to a breathing system, or to a ventilator, where the characteristics of those accessories can affect the basic safety or essential performance of the ventilator. ISO 80601-2-12:2011 is not applicable to me equipment or an me system operating in ventilation modes intended for patients who are not dependent on mechanical ventilation. ISO 80601-2-12:2011 is not applicable to me equipment or an me system intended for those patients who are not dependent on mechanical ventilation. If a clause or subclause is specifically intended to be applicable to me equipment only, or to me systems only, the title and content of that clause or subclause will say so. If that is not the case, the clause or subclause applies both to me equipment and to me systems, as relevant. ISO 80601-2-12:2011 is not applicable to continuous positive airway pressure (CPAP) me equipment, sleep apnoea therapy me equipment, home healthcare environment ventilators, ventilatory support me equipment, emergency and transport ventilators, anaesthetic ventilators, high-frequency jet ventilators (HFJVs) and high-frequency oscillatory ventilators (HFOVs). ISO 80601-2-12:2011 does not specify the requirements for me equipment that is intended solely to augment the ventilation of spontaneously breathing patients within a professional healthcare facility. ISO 80601-2-12:2011 does not specify the requirements for ventilators or accessories intended for anaesthetic applications which are given in ISO 80601-2-13. ISO 80601-2-12:2011 does not specify the requirements for ventilators or accessories intended for home care ventilators for ventilator-dependent patients which are given in ISO 10651-2. ISO 80601-2-12:2011 does not specify the requirements for ventilators or accessories intended for emergency and transport which are given in ISO 10651-3. ISO 80601-2-12:2011 does not specify the requirements for ventilators or accessories intended for home-care ventilatory support devices which are given in ISO 10651-6."
Scope of ISO 80601-2-70:2015 (No line breaks in the copy sorry)
"This particular standard is applicable to the BASIC SAFETY and ESSENTIAL PERFORMANCE of SLEEP APNOEA BREATHING THERAPY EQUIPMENT, hereafter referred to as ME EQUIPMENT, intended to alleviate the symptoms of PATIENTS who suffer from obstructive sleep apnoea by delivering a therapeutic breathing pressure to the respiratory tract of the PATIENT. SLEEP APNOEA BREATHING THERAPY EQUIPMENT is intended for use in the HOME HEALTHCARE ENVIRONMENT by LAY OPERATORS as well as in professional healthcare institutions. This particular standard excludes SLEEP APNOEA BREATHING THERAPY EQUIPMENT intended for use with neonates. This particular standard is applicable to ME EQUIPMENT or an ME SYSTEM intended for those PATIENTS who are not dependent on mechanical ventilation. This particular standard is not applicable to ME EQUIPMENT or an ME SYSTEM intended for those PATIENTS who are dependent on mechanical ventilation such as PATIENTS with central sleep apnoea. This particular standard is also applicable to those ACCESSORIES intended by their MANUFACTURER to be connected to SLEEP APNOEA BREATHING THERAPY EQUIPMENT, where the characteristics of those ACCESSORIES can affect the BASIC SAFETY or ESSENTIAL PERFORMANCE of the SLEEP APNOEA BREATHING THERAPY EQUIPMENT. MASKS and application ACCESSORIES intended for use during sleep apnoea breathing therapy are additionally addressed by ISO 17510. 3) Refer to Figure AA.1 for items covered further under this standard. If a clause or subclause is specifically intended to be applicable to ME EQUIPMENT only, or to ME SYSTEMS only, the title and content of that clause or subclause will say so. If that is not the case, the clause or subclause applies both to ME EQUIPMENT and to ME SYSTEMS, as relevant. HAZARDS inherent in the intended physiological function of ME EQUIPMENT or ME SYSTEMS within the scope of this standard are not covered by specific requirements in this standard except in 7.2.13 and 8.4.1 of the general standard.
This particular standard is not applicable to high-frequency jet ventilators (HFJVs) or high-frequency oscillatory ventilators (HFOVs).[16] This particular standard does not specify the requirements for ventilators or ACCESSORIES intended for critical care ventilators for ventilator-dependent PATIENTS which are given in ISO 80601-2-12. This particular standard does not specify the requirements for ventilators or ACCESSORIES intended for anaesthetic applications which are given in IEC 80601-2-13. This particular standard does not specify the requirements for ventilators or ACCESSORIES intended for home care ventilators for ventilator-dependent PATIENTS which are given in ISO 10651-24) . This particular standard does not specify the requirements for ventilators or ACCESSORIES intended for emergency and transport which are given in ISO 10651-35) . This particular standard does not specify the requirements for ventilators or ACCESSORIES intended for homecare ventilatory support devices which are given in ISO 10651-66) . This particular standard is a particular standard in the IEC 60601-1 and ISO/IEC 80601 series of standards. "
------------------------------
Leonard (Leo) Eisner, P.E.
Principal Consultant, Eisner Safety Consultants
Phone: (503) 244-6151
Mobile: (503) 709-8328
Email: Leo@EisnerSafety.com
Website: www.EisnerSafety.com
Original Message:
Sent: 03-Sep-2017 18:21
From: Dan O'Leary
Subject: IEC 60601 series v. ISO 80601 series
I was doing some research on CPAP machines because somebody raised an issue about a requirement in IEC 60601-2. I couldn't address the question because the citation seemed incomplete. I expected one of the form IEC 60601-2-n.
I looked on the IEC website and entered CPAP in the search engine. It took me to ISO 80601-2-12. I went to the ISO website and it tells me that the previous version was IEC 60601-2-12:2001, but it is now obsolete, and replace by replaced by ISO 80601-2-12:2011.
This raises questions.
Is there a plan to convert some or all of the IEC 60601-2-n standards to ISO 80601-2-n standards? If not all, which ones? When would the conversion be complete?
Test Report Form IEC60601_2_12D applies to IEC 60601-2-12:2001. The IEC website says there is no test report form for ISO 80601-2-12:2011. What is the future of test report forms when a standard converts from IEC to ISO?
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Dan O'Leary
Swanzey NH
United States
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