I have some fundamental problems with the concept of a certification having an Expiration Data, or a Recalibration Date.

My problems begin with the basic fact that a certification is only valid at the moment the instrument is being checked. By the time the certification has been typed the instrument may already be out of calibration. Some may call this an absurd statement, but I contend that it is absolutely true.

Let me give some examples:

1. A Lab Tech finishes his calibration work on an instrument, leaves the tool on his bench and goes to his computer to transfer his measurement data to the certificate. While he is away from his workbench a co-worker accidentally knocks the instrument onto the floor. For reasons know only to the co-worker, he picks-up the instrument and replaces it on the workbench and does not report the incident. The fall, in this situation has put the instrument out of wack and invalidated the calibration as it was being typed.

2. A properly calibrated instrument has been packaged for shipping back to the owner of the tool. The shipment is by overnight courier. During the return trip the instrument passes through several extreme temperature situations: Heated by sun baked delivery truck; Frozen in the belly of a high flying airplane; Heated again in another truck turned oven by the sun. The result is that critical components of the instrument, which are held in tension and locked in place, are loosened by thermal expansion and contraction allowing the tool is no longer at the certified set size.

3. Upon arrival at the owner’s factory, the Receiving Clerk, in the process of unpackaging the instrument, handles it roughly by whatever untoward method you can imagine. He never reports the possible damage to the tool because it looks just fine. Regardless, the instrument has been rendered inaccurate by his actions.

4. A properly calibrated thread plug gage is placed into service with the instructions to the user to measure every 100th part. The operator, being a good employee in his eyes, figures that if one part measured in a hundred is good, every part measured is lots better. A week later the poor thread plug gage is, while unnoticeable to visual inspection worn to a nub. It is returned to the crib and stored for future use even though it has been worn beyond its limits.

Let me say that these situations may or may not cause a tool to fall out of calibration, and I would hope that many instruments can handle some abuse without going out of wack. Let me also say that the opportunity for an instrument’s settings to be silently altered are numerous and beyond total control. It is for these reasons that placing an Expiration Date on a certification, in my opinion, should be avoided like the plague.

Yes, we all know that an Expiration Date is for reference only. Yes, we all know that all instruments should be validated for function frequently. Or do we? To many not as deeply involved in the calibration of instruments and not familiar with the fragility of measurement instruments, an Expiration Date gives the false impression that all will be fine until that date is met. It might even be argued that an Expiration Date is a guarantee of performance up to that date, which is something that no calibration laboratory would be willing to assure. For these reasons I contend that no certification should ever have an Expiration Date. A Recalibration Date is nearly as bad. It implies the same thing as an Expiration Date with the subtitle differences being lost on the masses.

My preference would be to have no time based calibration cycle stated on a certification. Calibration cycles are best determined based on usage. But, customers have become trained to use time based systems, and expectant of such data being found on the certification. Calibration Laboratories, wanting to meet customer requirements, to keep the customer happy, have complied and placed such specious data on he certification.

The solution, on the certification any recalibration date should be identified as ‘suggested’. Further caveats should also be included in the fine print as to proper determination of calibration cycle or some such other disclaimer against the absolute value of any given suggested, time based, recalibration date.

I agree with everything you have said here. Since there is no "perfect" way to do calibration at a reasonable cost, I use it as a fence. Once a device is proven to be in calibration everthing checked prior to that calibration is considered acceptable. As you stated, a gage can go out at any point during the inspection process. It is not feasable to calibrate a gage after each measurement so we keep track of what product is checked by which tool. At the end of a production run the inspection tools are rechecked for accuracy. Not recalibrated! We send our inspection tools out every 6 months for outside calibration to verify our in house measurements. When they are proven accurate we approve the job. The extra 10 or 15 minutes this takes for each job has paid huge dividends over the last few years.

Doug

I would tend to treat an expiration date as a maximum time, not necessarily a guarantee.

For example, the egg salad in my fridge has an expiration date a week from now. But if I leave it out of the fridge overnight, I'd throw it out - even if it is still a week to the stated expiration.

So an instrument - if shipped and stored and used as expected - should be good up until the expiration data. Eventually the calibration will fail - due to normal use, corrosion, evaporation, etc. The due data (IMHO) is an effort to estimate these sorts of expectations.

If not shipped and stored and used as expected, then it could well go out of calibration earlier. As you say, it is hard (or impossible) to know if it has been handled appropriately. That is where in-house checks help to ensure it is still operating as expected.


Tim F

Let me give a reply that sounds like I am talking out both sides of my mouth.

On the one hand, a Certification and due date are not in any way a guarantee of how long the instrument will stay within spec. When an instrument is calibrated/certified, it is returned to the owner, and if anything happens between the cal date and due date, the lab is not liable for it's remaining within tolerance.

On the other hand, the due date (or let me shift gears and use the term "interval" for the remainder of my reply) is based on some valid reasoning. The calibration interval is the amount of time to a defined statistical confidence level that an instrument can be expected to remain within tolerance. This means that the assignement of a due date is based on a predicted interval of time that the instrument will "probably" remain in tolerance. 95% is a common confidence, based on statistical probability.

There are other ways to assign or adjust intervals (but I won't go into all that now). So the assignment of a due date on a certificate means who ever assigned it is stating (if using the statistical method), that the unit will have a 95% probability (using my example above) of remaining in tolerance until that date.

So there is valid thought that goes into assigning the due date.

I would have to go on record that a certification (with some exceptions) must have a due date on it. This is a part of what a certificate of calibration is - a prediction of how long an instrument will probably remain in tolerance.

I would have to go on record that a certification (with some exceptions) must have a due date on it. This is a part of what a certificate of calibration is - a prediction of how long an instrument will probably remain in tolerance.

I agree, and thanks to Wayne for raising an interesting topic.

We need to not forget that part of the information we receive from calibration is the "as found" condition, and we should be using it wisely. If, for example, we find that 6-inch calipers in similar use consistently need adjustment when being calibrated, we need to (A) shorten the interval, and (B) investigate the situation. Are the calipers being abused? Are they worn such that maintaining set points is impossible?

The problem, as I see it, is one of education; people need to know that the due date on the label represents a maximum and not an absolute value. This seems obvious, and I think most people understand that there is risk in assuming that devices are properly calibrated when the state of calibration isn't intuitive. But you can't get people to use measurement equipment prudently by masking significant information.

For my part, I had only the date of calibration/certification put on the label or tag, never a due date. To my mind, the interval between calibration/certification dates doesn't even start until the gage/instrument is put into service. Some gages might lay in a drawer in a temperature-controlled lab for 6 months before going into use. I kept track of usage in a database keyed to serial numbers of each gage or instrument. If the gage got excessive use, it got checked more frequently in-house to confirm it was still within tolerance.

I have had some gages go out of tolerance very quickly. I heard an apocryphal story about employees using a 2-inch micrometer as a nut cracker!
:notme:

Let me give a reply that sounds like I am talking out both sides of my mouth.

On the one hand, a Certification and due date are not in any way a guarantee of how long the instrument will stay within spec. When an instrument is calibrated/certified, it is returned to the owner, and if anything happens between the cal date and due date, the lab is not liable for it's remaining within tolerance.

On the other hand, the due date (or let me shift gears and use the term "interval" for the remainder of my reply) is based on some valid reasoning. The calibration interval is the amount of time to a defined statistical confidence level that an instrument can be expected to remain within tolerance. This means that the assignment of a due date is based on a predicted interval of time that the instrument will "probably" remain in tolerance. 95% is a common confidence, based on statistical probability.

There are other ways to assign or adjust intervals (but I won't go into all that now). So the assignment of a due date on a certificate means who ever assigned it is stating (if using the statistical method), that the unit will have a 95% probability (using my example above) of remaining in tolerance until that date.

So there is valid thought that goes into assigning the due date.

I would have to go on record that a certification (with some exceptions) must have a due date on it. This is a part of what a certificate of calibration is - a prediction of how long an instrument will probably remain in tolerance.

I would also agree to this statement. Use to work for a Machining/Millwright company. Our standard practice was to check tools such as I/S and O/S mic's before use. Furthermore, we (for the most part) had two sets of standards for the QA system. I agree that a calibration sticker or certificate is no promise that the tool is within spec, however it does prove to the customer that your QA program is important enough to ensure best practice.


JMT Tim

A 'Due Date' on a calibration certificate is one thing. What about a 'Due Date' on calibration stickers which most companies put on individual measurement instruments?

Our calibration agency calibrate instrument but does not give next due calibration date since they say that it is lab that decide what should be the due date. Why? becuase lab is user of that equipment not the calibration agency.
Yet they put next due calibration for physical equipment like weighing scale, meaureing tape etc.:thanks:

Wayne, thank you. It is always appreciated having posts that make you think.

Just my opinion:

1. Should you never put a recall/expiration date on a certificate?

It depends on the customer. I, for one, do not want recall dates, as I have my own system from historical data which I use for recall. A date on the certificate is just something else to explain.

For many customers I have done work for, a recall date is yet another matter. They have no system, and rely on the objectivity/advice of the calibration vendor for the date. Do I know that well? No. But the customer has confidence in the little piece of data being on the sheet. Most of the time the recall is agreed upon with the customer, and it's on there for their convenience.

2. If you put the date on there, what should it be based upon? I would like to say that it is always based on compilation of data, accounting for uncertainty, etc., but most of the time, it isn't. It is based on history; not only of the instrument, but of the vendor performing the calibration, and the variables mentioned by Wayne.

A calibration activity is similar to an audit: on this date, this is what I found. The calibration lab cannot be responsible (to an extent) of what happened before and after the calibration. The individual with the Unit Under Test has the responsibility of controlling (or measuring) the variables.

I really never have viewed recall dates as anything more than a reminder tool. Rather, a suggestion for the recall system that simply states, "unless anyone has a more brilliant idea, why don't we calibrate this next time at XX/YY". If instruments did not have a recall date on the stickers, it would be profoundly difficult to have half of them returned for calibration. Should the system be robust than that? Probably. But sometimes, I take whatever I can get.

A 'Due Date' on a calibration certificate is one thing. What about a 'Due Date' on calibration stickers which most companies put on individual measurement instruments?

Regarding 'Due Date' on the calibration certificate, I agree with wayne for a different reason. Even while considering that the mmd reaches the user in 'as calibrated' state, the calibration lab has no knowledge of the use conditions or frequency to realistically define a 'Due Date'. We had a practice of defining our own calibration frequency and even our own acceptable error limit. We used to correct and initial the calibration certificates before filing them for record.

The 'Due Date' stickers on the instruments - again, in our case, we had put the responsibility of using an mmd under (supposedly) valid calibration on the user. The stickers / colour codes were a communication tool to let the user know when the mmd is supposed to be returned to metrology. This, so far,is the best recall control I have encountered.

I have some fundamental problems with the concept of a certification having an Expiration Data, or a Recalibration Date.

This thread has mainly talked about calibration of instruments, and I understand why, but let's look at our other certificates with expiry dates......what about the certification of our QMS? Should that have an "Expiry" date?

Like a gauge can be dropped as soon as calibrated, so can elements of a business management system, as soon as an auditor walks out of the door!

I know this is not maybe quite the same thing and that regular audits are part of maintaining a system, but an expiry date suggests a supplier is only competant as long as their certificate is in date!!!! The exipry date is like a big red deadline, we all know that the date means it's time for another audit, but it is that psycological effect of having something that has "expired"!!!

Does any one have a certificaiton body that doe not use "Expiry"? Something more along the lines of "System Review Date"? I know this is maybe tit for tat, but why is it any different than a cert on a gauge?

I agree with all the scenerios that Wayne put forward that at any time any gage may be out of spec. I am one that puts calibration done and due dates on all equipment. This is more of a recall system used to ensure a gage doesn't go past the internal interval that has been placed on the gage for accuracy. I will give an example.

1. A gage is lost/misplaced on the floor for a few months. The gage has a 1 month calibration interval. The gage finds its way back from the other dimension it has been in and without a due date on the gage the operator has no clue it is due for calibration. A lost gage report has been done and has been labeled as lost in the system. So basically wrote off as lost by everyone. (It is hard enough to get the operators to look at the due date on the sticker much less expect them to keep up with the intervals of calibration.)

Now it is our responsibility in the gage labs to ensure that we adjust intervals to balance the delicate area between cost savings and ensure accurate readings. An example would be I have 6" calipers on the floor that get calibrated every month were as I have some setups that have 6" calipers that only get calibrated every 3 months. This is were the "as found" condition comes into play. On the other hand I have some black/white light sensors that Gould Bass recommends only calibrating every 6 months and I have to have them calibrated every 3 months to ensure they stay within spec.

The work insructions for all gages express in detail that if any thing is out of the ordinary the gage needs to be rechecked by the gage lab. We have a "dropped gage" work instruction also.

So basically we have to be confident in our operators to bring to our attention any out of the ordinary problems with a gage. Also the due date is just a way to let the operators know that they are for sure not to use the gage after that date.

:2cents:

Manix

Errr - you must not use the archaic 3 syllable English word "expiry" in this forum. :)
You must add a syllable and take a few extra milliseconds to write "expiration" to be understood here:rolleyes:

Manix

Errr - you must not use the archaic 3 syllable English word "expiry" in this forum. :)
You must add a syllable and take a few extra milliseconds to write "expiration" to be understood here:rolleyes:

I understood him - but then my Mum's from the Isle of Wight. :lol:

You have to love the English language - so many ways to say the same thing;)

I noticed that Fluke doesn't put a due date on our 5500A calibrators when we send them in for repairs. It is up to us to determine when we want to re-verify it, whether we want to use the 90 day specs or the 365 day specs. For us, there's no being babied in a tightly controlled lab environment here, they get subjected to a bumpy ride in a smoking hot trailer, then get subjected to thermal shock whenever we park, hook up shore power and turn the A/C on full blast. Same goes with all the other "lab grade" instruments we drag on-site every week of the year to refineries, power plants, pulp mills, etc. But we self-test and spot-check everything once we get to the job site and have everything hooked up and the equipment has had ample time to stabilize, and add to the uncertainties if the temperature exceeds a certain number of degrees since the time of calibration. Also, we do verify the accuracy of the equipment in house once a year (some more often), and usually we find that they hold their specifications for years on end without needing to be adjusted, despite the torture they get whenever they get taken on-site. We try to meet the cal due "deadline" we set, but in case the equipment is out on the road, we have a process in place for extending the due date.
Just my :2cents: ...

This thread has mainly talked about calibration of instruments, and I understand why, but let's look at our other certificates with expiry dates......what about the certification of our QMS? Should that have an "Expiry" date?

Like a gage can be dropped as soon as calibrated, so can elements of a business management system, as soon as an auditor walks out of the door!

I know this is not maybe quite the same thing and that regular audits are part of maintaining a system, but an expiry date suggests a supplier is only competent as long as their certificate is in date!!!! The expiry date is like a big red deadline, we all know that the date means it's time for another audit, but it is that psychological effect of having something that has "expired"!!!

Does any one have a certification body that doe not use "Expiry"? Something more along the lines of "System Review Date"? I know this is maybe tit for tat, but why is it any different than a cert on a gage?


Ok,
Then if the problem is using the "Expiry Date" or "Certification Date" maybe the terminology needs to be changed. I see these types of terminologies are used interchangeability, of course two minutes after a piece of equipment has been calibrated, there is no guarantee that it is still in spec. As in you oil in you car you check your oil every time you gas up and you change your oil every 4K miles, but does that mean that the oil is out of spec? In most cases it probably just fine for another 1K miles. However, if you do not check it or change it will eventually destroy the motor.

At the end of the day a expiry date is not for the user of the equipment it is for the customer to make him/her feel all warm a fuzzy about your quality system.

JMT

Tim

In my opinion.....

Expiration dates should be determined by the user and not the calibration service provider. There may be no need for them. The calibration service provider should only identify expiration dates if they are given by the customer (user of the tool.)

Calibration is one step in understanding a tool and the measurement system. Linearity, bias, stability, repeatability and reproduceabilty need to be considered when trying to evaluate the "shelf life" of a calibration / usefulness of a tool.

Calibration alone should not give the user total confidence on the tool.

"As Found" data should be provided by the calibration service provider to better understand the tool's stability.

Regards,

Dirk

In putting together a presentation on ISO/IEC 17025 2005, which is at the heart of this matter, I see that in section '5.5 Equipment' it speaks of "intermediate checks...needed to maintain confidence in the calibration status of the equipment." Hiow about doing that?

As with many situations regarding compliance to some requirement, it's often done without care and consideration of data. The idea of a calibration status sticker is no more or less than the oil change shop putting a sticker on your windshield (windscreen) telling you to change the oil in another 3,000 miles. It's only a suggestion and the oil should be monitored by 'dipping' it and making sure there's still some in the engine! (O.K, so I used to run old English cars, which leaked oil.......:lol:)

As in you oil in you car you check your oil every time you gas up and you change your oil every 4K miles,

change the oil in another 3,000 miles. It's only a suggestion and the oil should be monitored by 'dipping' it and making sure there's still some in the engine! (O.K, so I used to run old English cars, which leaked oil.......:lol:)

A little :topic:, but what cars are you guys driving? Even my first car (1979 Ford Fiesta) had 6K miles between oil changes! My current car has 10K and I know a lot of new cars are long service life and can go upto 25k before an oil change is needed!

It is a good analogy though, you can't forget about it until the next service as you may run out of oil, but perhaps the new longer service intervals, may actually make people do that, completely forget about it for 25000 miles and then wonder why they are on the hard shoulder on the M25 in a cloud of smoke!!!!!!

Americans have been bullied into believing that oil changes are necessary every 3000 miles, rather than following the manufacturer's recommendations. Toyota recommends 7500 miles between changes for my Camry under normal service, and 5000 miles under heavy service. Of course, that doesn't mean you don't check the oil level between changes.

The truck I used to have had a check engine light that turned on after 50,000 miles, so I took it to the dealer, and they did diagnostic tests and said there was nothing wrong, that the light comes on after 50,000 miles as a reminder to have it serviced. Then they charged me 50 bucks to turn the light off. :mad: But that's exactly what happens with some electronic test equipment nowadays, it'll actually say on screen that the calibration is due, and you have to send it out to have it reset, whether the instrument is reading in tolerance or not. And some metrology software, such as Fluke's MET/CAL won't let you run a calibration procedure if one of the instruments that it uses and reports on its printed certificates has expired. Imagine if your car wouldn't let you start it if the oil hadn't been changed past its recommended interval! :mad:

We had a major "thing" about this after our latest 17025 audit earlier this year (well, late last year but it took till Feb to conclude.)

My boss/bosses want the date because they think Mr Customer will only return their calibration standards and/or instrument if we have an expiration date. I say nonsense, they wait as long as they want anyway. Some put their own stickers over ours too.

I changed our cert's to have N/A in the Due Date area, with an explanation about how things can affect the calibration over time. But left a space to put a date if the customer wanted it. I thought the bosses agreed to this during the audit.

Boy was I wrong, they threw a fit I had done this. I had to redo about 30-40 cert's with the regular 1yr or 6mo interval and explain why to the customer.

Now we are using the clause that says the customer agrees to it, and basically if it's been going on for 5 years at 1yr intervals, that's what he's agreeing to. I put on the workorder somewhere the description of the item and "annual certification". If they pay the bill, they've agreed to it.

Cheesy, but the bosses are happy. Whatever...

I agree, and thanks to Wayne for raising an interesting topic.

We need to not forget that part of the information we receive from calibration is the "as found" condition, and we should be using it wisely.

The problem, as I see it, is one of education; people need to know that the due date on the label represents a maximum and not an absolute value. This seems obvious, and I think most people understand that there is risk in assuming that devices are properly calibrated when the state of calibration isn't intuitive. But you can't get people to use measurement equipment prudently by masking significant information.

Our calibration forms/ certs (one and the same to us) contain full calibration data as well as the defined user range including min and max user loads and resolutions. They also do contain the contracted intervals of calibration and the month/year of next inspection.

Customer education is the key to care and maintenance of equipment.
Many standards require interim checks of equipment. We also suggest this to our customers who have sensitive equipment.
Type and correct use of the equipment will establish its ability to hold calibration.

Our due dates are simply a statement to the customer we will be back in this month and year to calibrate unless you call us back for some reason. (user suspicion device is off, user broke it:mg:, starting new run and need documentation)

Customer has everything they need on one piece of paper for each scale including when we will be back. This enables them to do their due diligence as required. BTW dates are on stickers as a reminder to customer and apparently auditors and such like to see them.

Dear Mr. Wayne,

Thanks for this interesting topic. To be honest, I am not able to take position as I feel both for and counter points are right in their own perspective.

Yes, I do agree that there is no guarantee that the calibration is valid after it leaves the lab and so, the relevance of expiry date is gone. But, I also agree that the expiry dates should be specified on both certificate and equipment as it indicates to the user about the risks involved when the equipment is nearer to re-calibration/ re-inspection.

When we agree that the calibration due date is not required on the certificate & equipment, in one way we are saying that the trust worthiness of that equipment is gone and we are not sure of the results of testing/ measurement. This is not a healthy sign and it results in blame game when process inspection indicates the non-conformance in the product.

Definitely, internal checks are required but one can not apply to all testing/ inspection/ measuring equipment. It should be on case to case basis and depending upon the use, kind and volume of production, the frequency of recalibration could be increased/ decreased.

If any error is detected during the recalibration and at-least we could initiate the corrective action immediately and minimize the damage to the product/ Company reputation and rectify the defective products as we can trace them by specifying the IMT equipment ID # on the quality record. Probably that might be the reason why ISO 9001:2000 Clause 7.6a requires recalibration at specified intervals.

I personally feel that the Quality personnel are best to judge the interval as they know the usage and importance of testing.

Rajeev

Calibration status stickers with due dates affixed on instruments is for the user to know when the calibration date is due.
According to 17025, the due date for calibration need not be specified in the calibration report

For my part, I had only the date of calibration/certification put on the label or tag, never a due date. To my mind, the interval between calibration/certification dates doesn't even start until the gage/instrument is put into service. Some gages might lay in a drawer in a temperature-controlled lab for 6 months before going into use. I kept track of usage in a database keyed to serial numbers of each gage or instrument. If the gage got excessive use, it got checked more frequently in-house to confirm it was still within tolerance.

I have had some gages go out of tolerance very quickly. I heard an apocryphal story about employees using a 2-inch micrometer as a nut cracker!
:notme:

Is this formula of not mentining the next due date of calibration is for all kinds of equipment or there is any exceptions?:thanks:

whoa, whoa, whoa.......
17025 standard CLEARLY states that a calibration due date CANNOT be reported on a certificate or sticker unless requested by the customer. If you are putting due dates on the equipment that wasn't OK'd by the customer you are breaking the rules.

I think I saw a thread regarding calibration intervals. Are we not basing our recommendation to the customer on past performance??? If a device is tested every week and it only fails once a year, are we not suggesting that the customer lengthen the calibration interval to 90 or 180 days??

If a device is tested once every 2 years and hasn't passed a test in 10 years, then the customer should be STRONGLY encouraged to shorten their cal interval. It is the customer's responsibility to set the calibration interval. A 17025 accredited lab CANNOT state a due date without the customer's approval.


Also- Are we the only lab that has this statement on our certs?: "Documented results contained within this calibration certificate relate only to the artifacts calibrated on the date listed."

Also- Are we the only lab that has this statement on our certs?: "Documented results contained within this calibration certificate relate only to the artifacts calibrated on the date listed."

You calibrate artifacts?

You calibrate artifacts?

I was really expecting to see a funny face after that question, Jim.

Or, wait, this is better....:sarcasm:

I'll bite anyway....
Yes, we refer to items that are in our lab to be calibrated as artifacts. That is, in written procedures and statements such as the one above. Not in daily conversations, of course... We're not that crazy.:bonk:

I was really expecting to see a funny face after that question, Jim.

Or, wait, this is better....:sarcasm:

I'll bite anyway....
Yes, we refer to items that are in our lab to be calibrated as artifacts. That is, in written procedures and statements such as the one above. Not in daily conversations, of course... We're not that crazy.:bonk:

Sarcasm? Moi??? I've just never seen the word used that way. Carry on.

"Documented results contained within this calibration certificate relate only to the artifacts calibrated on the date listed.":applause:Good move to put this on your certification. Very honest approach.

Good morning,
What I can do if we bought several mesuring devices to a distribuitor and the calibration certificates are expired, the devices are brand new, Do I need to create a letter stating the date that we started using the devices and use date date as our calibration date; Do I need to include purchar order as evidence/back up in order to justify why using a differerent date vs certificate date? Please advise, I don't know whant is the best way to deal with this situation.
Thanks for your help.

Do you have such type of letter to share?
AC
Thanks

Good morning,
What I can do if we bought several mesuring devices to a distribuitor and the calibration certificates are expired, the devices are brand new, Do I need to create a letter stating the date that we started using the devices and use date date as our calibration date; Do I need to include purchar order as evidence/back up in order to justify why using a differerent date vs certificate date? Please advise, I don't know whant is the best way to deal with this situation.
Thanks for your help.

Do you have such type of letter to share?
AC
Thanks

What I would do in this situation, is: Send them out for Calibration.

One thing I have learned is not to always accept the OEM's certificate of Calibration.

There are times when you can get away with using a delayed start date for a cal interval. However, generally, in an audit, you would have the burden of proof to demonstrate to the auditor why during the intervening time the accuracy would not have degraded in the instrument.

Items which change value strictly due to use versus passage of time, that may be acceptable. In a previous employer, we used high temperature thermocouples which have a life span of about 6 months when used at around 1000 to 1200 Degrees Celsius. However, that aging was due to the high temperature. So we had a document in our quality system stating that our procedure was to place them in environmentally controlled storage. Then, when they were given to the user, the calibration interval began. This could have been true for items which only age/drift/change during use, and definitely do not change in controlled storage.

But for everything else, the cal date is when it was actually calibrated.

My recommendation would be as in the previous post: to either live with the existing cal date/due date, or get them re certified.

As to the validity of the OEM certificate, some are good and some are not. I am currently in a high volume lab with pretty strict guidelines in that regard. We review every one of the OEM certificates on new instruments. Quite often they are fine (from the large, reputable OEMS (such as Fluke, Tektronix, Agilent, Mitutoyo, etc.). But some are not. I would weigh the validity of the particular certificate as to whether to accept it.

Sorry if any of this is bad news. Just have to shoot as straight as I can, and try to help.

Good morning,
What I can do if we bought several mesuring devices to a distribuitor and the calibration certificates are expired, the devices are brand new, Do I need to create a letter stating the date that we started using the devices and use date date as our calibration date; Do I need to include purchar order as evidence/back up in order to justify why using a differerent date vs certificate date? Please advise, I don't know whant is the best way to deal with this situation.
Thanks for your help.

Do you have such type of letter to share?
AC
ThanksI'm not exactly clear about what timetable events followed.


Were the certificates expired when you obtained the devices? (If yes, you should have gotten a BIG discount, which would cover cost of updating calibration) - many folks have operations where devices are for "intermediate measuring activity" and only the FINAL devices are kept calibrated - not exactly best practice, but often acceptable, so they are natural market for discounted, out-of-date devices.
If the devices were NOT out-of-date when you acquired them, it is your organization's responsibility to keep them calibrated with up-to-date certificates if your own QMS (Quality Management System) requires calibrated devices.

If these devices are used to approve product, they probably should have current certificates of calibration. If they have NEVER been used, odds are they can merely be rechecked by the original certificate signer and updated, without requiring costly adjustments or refurbishing to bring into calibration - price "could" be much more reasonable than going to a new entity to obtain a certificate.

Good luck! Tell us what you ultimately do and whether the pricing was fair or exorbitant.

I strongly agree with Wes's first point. Whether you believe the cert to be accurate or not (even if it up to date). That cert is part of your purchase and thus you have paid for it. If you went to buy another type of equipment or device wouldn't you expect it to be in working condition for its intended use? Of course you would, so the same would hold true in this case. I would guess the use of this equipment is verification and thus calibration is a major part of that. I would also ask your distributor what their FIFO policy is. I don't know that this would be a concern but the answer would be interesting.

The points on your organization are accountable to audit criteria regardless of the root cause also appear to be strong.


Good Luck

One thing that has been mentioned (thanks AndyN) is accreditation under ISO/IEC 17025.....if a cal provider is not accredited or is ISO 9K, there is no real oversight with respect to the due date issue. In fact, if the lab is only ANSI/NCSL Z540-1-1994 which is self-declared, that standard requires the due date be provided.....otherwise the customer (user of the instrument) has to monitor and control this.....in my experience there are few Metrology professionals at end user organizations and especially at smaller organizations, hence there may be insufficient knowledge to interface with the cal provider.....remember, Quality and Metrology are related but are not the same!

Under ISO/IEC 17025, Clause 5.10.4, due dates cannot be put on without prior agreement by the customer, and the ABs oversee this.

Hope this helps clarify what is or is not allowed.

What I can do if we bought several measuring devices to a distributor and the calibration certificates are expired, the devices are brand new, Do I need to create a letter stating the date that we started using the devices and use date as our calibration date; Do I need to include purchase order as evidence/back up in order to justify why using a different date vs certificate date? Please advise, I don't know what is the best way to deal with this situation.Anerol C; I would point you back to the first post that started this thread: ... the basic fact that a certification is only valid at the moment the instrument is being checked. By the time the certification has been typed the instrument may already be out of calibration....In this specific situation, you know by virtue of the provided calibration certificate, that it has been some time since the tools were manufactured. It is for you to determine if they deteriorate with the passage of time. You also know that the tools are “brand new”; that they are in original packaging and appeared to no signs of use or abuse.

It is up to you, as the local Quality Professional to determine if the tools need calibration. If you decide not to have the tool checked, it would be best to attach to the certificate a note describing your decision process, with any appropriate documentation, because you may need to substantiate the logic behind your decision.

Basically I would say: When in doubt; send them out.What I would do in this situation, is: Send them out for Calibration. One thing I have learned is not to always accept the OEM's certificate of Calibration.Again, remembering the first post, calibration expiration dates are worth little. Whenever you purchase a new tool, regardless of the supplied calibration certificate, you should evaluate the tool to determine if local verification is required.

... you should have gotten a BIG discount, which would cover cost of updating calibration ... ... That cert is part of your purchase and thus you have paid for it.... I would guess the use of this equipment is verification and thus calibration is a major part of that.As long as the type of tool is such that it does not deteriorate with age, and knowing that any certification is only really valid when the tool was verified, regardless of any applied “expiration date”, sending a new tool to your approved laboratory upon arrival is just prudent. The initial calibration of the new tool will give you a base-line calibration, and the cost of calibration should not that BIG of an issue. It will be an expense that you will incur several times during the life of the tool.

I'm not exactly clear about what timetable events followed.


Were the certificates expired when you obtained the devices? (If yes, you should have gotten a BIG discount, which would cover cost of updating calibration) - many folks have operations where devices are for "intermediate measuring activity" and only the FINAL devices are kept calibrated - not exactly best practice, but often acceptable, so they are natural market for discounted, out-of-date devices.
If the devices were NOT out-of-date when you acquired them, it is your organization's responsibility to keep them calibrated with up-to-date certificates if your own QMS (Quality Management System) requires calibrated devices.

If these devices are used to approve product, they probably should have current certificates of calibration. If they have NEVER been used, odds are they can merely be rechecked by the original certificate signer and updated, without requiring costly adjustments or refurbishing to bring into calibration - price "could" be much more reasonable than going to a new entity to obtain a certificate.

Good luck! Tell us what you ultimately do and whether the pricing was fair or exorbitant.

Yes some of the certificates were expired when we received the equipment.
What I think I will do is get a deviation to use them while we can send them out to calibration, the issue is that some of them are the only equipment in the whole plant, so I think we need to get a new one then send the equipment with expired certificate to calibration. I think this is the only thing that I can do if we are going to have the registrar coming to our plant in about one month.
Thanks
AC

It is up to you, as the local Quality Professional to determine if the tools need calibration. If you decide not to have the tool checked, it would be best to attach to the certificate a note describing your decision process, with any appropriate documentation, because you may need to substantiate the logic behind your decision.


Also while equipment is calibrated I will attach the purchase order to the expired certificated along with the deviation. I hope this helps.
Thanks

Also while equipment is calibrated I will attach the purchase order to the expired certificated along with the deviation. I hope this helps.
ThanksBe sure to get matching Standards (master) for the equipment so you can do an on-the-fly check to determine the equipment matches your Standard.

For example, if it were a simple plug gage, get the matching ring.

For another example, ohm testers, a variety of Standard resistance pieces makes sense to assure equipment is in calibration - then at regular intervals, send BOTH equipment and the Standards out for calibration and certification.