We recently had our device tested to the appropriate ISO 60601 electric standards. During the testing one of the test engineers made the comment that to sell in Canada will need to incorporate the year and month of manufacture of the device in the serial and/or lot number. I have reviewed the CAN/CSA-C22.2 601.1-M90 (Canadian version of 60601) and cannot seem to find any such requirement. It seems that a requirement such as this would be a little too prescriptive. Is this test engineer correct in his interpretation or is this again an example of over interpretation?