ISO 13485 Calibration Requirements- Assess and Record validity Previous measuring results

[acejyke]

A newbie here.

I would like to ask your opinions on how to address this ISO 13485:2016 7.6 requirement : "the organization shall assess and record the validity of the previous measuring results when the equipment is found not to conform to requirements. The organization shall take appropriate action in regard to the equipment and any product affected"

- does this mean when the equipment is found to be non conforming to the specs or out calibration, we need to gather the previous measurement results for which this equipment was used for, and analyze the acceptability of the previous measurements and its effect to the product?
- the scope of previous results to gather- is it 1 whole year result or 2 years or just a few testing/usage results?
- will the "Investigation Report" sufficient as evidence of the assessment of the validity?

Hoping for your kind assistance - thank you.

 

[Tidge]

- does this mean when the equipment is found to be non conforming to the specs or out calibration, we need to gather the previous measurement results for which this equipment was used for, and analyze the acceptability of the previous measurements and its effect to the product?

Simply: Yes, for the entire interval since the last assessment of conformity.

With some subtleties:

• If you have an attributable cause for the non-conformity (e.g. calipers were dropped on Day X, and sent to lab where they were found to be non-conforming) you can make an argument that the data recorded with the instrument prior to the date of the attributable cause could be excluded from the assessment.
• It is common that equipment has some sort of "sanity check" applied prior to regular use. If there is evidence that this has been performed (and is often how some EQ are found to be non-conforming) it may be possible to triage the records requiring deep assessment.
• The assessment of unreliable measurements has to be wrapped up the greater assessment of risk acceptability for the product.

Digression follows....The final bullet point I offer is where I often see people tempted to speak out of both sides of their mouth, such as:

1. Those measurements at incoming are vital, because they are risk controls against the possibility of non-conforming product getting to our customers!
2. Those measurements at incoming aren't really that important, because we have a later in-process step that completely checks the suitability of the components to fulfill requirements!

My advice is to not over-exaggerate the necessity of certain steps in the formal 14971-based risk management process, and to properly weigh implemented risk controls in an RCOA. We can also apply general quality principles and eliminate steps/inspections that aren't providing value.

 

[BradM]

Hello there! Welcome to the forum!

Basically if one of your measurement instruments exceeded tolerance, there is a need to assess potential impact. Start with risk and potential impact.

Next, review the magnitude of the exceeded tolerance. Suppose its a thermometer with a tolerance of ±1°C and it was found to be... say 101.2°C when it was calibrated. What potential process impact will that have? If you're process tolerance is.. ±3°C, the incremental +.2°C is irrelevant.

Also, did the device fail at the point of use. If the thermometer was calibrated from.. -20°C to 200°C, and it's only used in the 60-80°C range, then review the calibration data at that use point. In my experience devices tend to fail at extreme points of range.

Anyway, just some thoughts.

 

[dwperron]

- does this mean when the equipment is found to be non conforming to the specs or out calibration, we need to gather the previous measurement results for which this equipment was used for, and analyze the acceptability of the previous measurements and its effect to the product?

Yes.


- the scope of previous results to gather- is it 1 whole year result or 2 years or just a few testing/usage results?

It goes back to the last time you have documented records that show the instrument was within tolerance. In most cases that means going back to the previous calibration, unless you have documented results of intermediate tests.


- will the "Investigation Report" sufficient as evidence of the assessment of the validity?

Yes.

 

[ChrisM]

I've been through this at a former place of work, device found to be out of spec at calibration.
You need to go back to when the device was last calibrated and found to be in spec and identify all products that were tested/measured by the out-of-spec instrument. Look at what BradM has posted above, check the range(s) where the instrument was used and how far out of spec it was in those ranges. Then look at the design spec for the devices tested and the test spec...... in our case, the test spec was narrower than the design spec, and the test results from the instrument that failed calibration taking into account the error found at calibration, were found to still lie within the design specification, so no recall was required as all affected devices would still have been performing to the product specification, although they had "failed" test when the measurement errors were taken account of.

This is worth bearing in mind when preparing test specs - build in a margin that will allow for more than uncertainty of measurement errors. It took us a lot of work and we prepared quite a large document of evidence of investigations etc, including the serial numbers of all potentially affected products, but it saved us a lot of expense on a recall (money and reputation)

 

[acejyke]

This forum indeed is big help.

Sorry I did not posted a reply immediately, but all you points were considered. We actually did a lot of work, and thankfully the auditor accepted it.

Thank you very very much