Re: Validity of IEC 60601-1 and IEC 60601-2-27 - An intermittent ECG event recorder
We assume here you are talking about Europe, in which case we still don't know the date. The latest IEC version of IEC 60601-2-27 was published in 2011, replacing the existing version IEC 60601-2-27:2005. The EN version corresponding to the 2011 edition is still not published, and without the EN version there can be no listing in the official journal. Until the final listing in the official journal, we can only guess the end of transition date.
But, assuming a normal timeline, 2014~2015 in Europe would be a reasonable guess for the time in which the old standard is withdrawn. Other regions/regulations would be case by case, but we can guess around the same time.
Anyway, up shot is, as there is an existing particular (IEC 60601-2-27:2005, EN IEC 60601-2-27:2006) that works with the 2nd edition (IEC 60601-1:1988, EN 60601-1:1990), you should continue to that set until the old particular is formally withdrawn.