IEC 60601-1 - 11.1.3 e) Test criteria - Temperature Measurements

[Roshan khandare]

Hello,
I have question on temperature monitoring test of 60601-1
11.1.3 e) Test criteria :
The maximum temperature of a part is determined by measuring the temperature rise of the part under test and adding it to the maximum allowed ambient temperature specified in the technical description (see 7.9.3.1).

In technical description operating temperature range is 10 to 50 degree specify. So max temp is 50 degree.
At a time of temperature measurement I tested the applied part temperature increase on 4 degree then we have to add the 4 degree on max operating temp range i.e 50 then maximum temperature of a applied part is 54 degree. As per table 24 on 60601-1 applied part temp is 43 degree then how can i concluded on that. Please help me.


Regards
Roshan

 

[Peter Selvey]

This is a problem or mistake in the general standard.

You can use IEC 60601-2-37 for ultrasounds as a reference. From memory (I haven't checked lately), they assume 35°C base (typical skin/surface temperature) and have a limit of 41°C. Also they allow that the body may cool the part. You can do a test in open air and measure the temperature rise is less than 6K then the result is OK, or if it is above 6K then test with a simulated body material. Usually the result is less than 6K so it's easy pass.
If the part is intended to apply internally, the reference should be 37°C and the limit is 4K rise.

Since it is going against the standard, the manufacturer can write this up in risk management as an alternate solution. But, I think it's such an obvious mistake that a test lab can also reasonably judge it is OK without risk management.

Most equipment is rated for 0-40°C operating. So that would mean any applied part with a >1K temp rise needs clinical justification. Which is crazy.

 

[Roshan khandare]

Dear Peter,
Thank you for reply. If manufacture gives the justification in risk management on temperature of applied part , so can we accept .
Means manufacture disclosed the max temp of applied part in risk management file and in the instructions for use.