An out-of-tolerance result means every measurement the instrument made since it was last known good is in question until the records show otherwise. The Out-of-Tolerance Impact Assessment (E02) walks the assessment from the event to every lot, and says when it can close. Open it the day the certificate comes back.
- Record the event. The instrument, the as-found data, the largest error and its direction, and the last known good date. Quarantine the instrument or record why it is back in service after adjustment.
- Set the window. From last known good to the date it was found. If the instrument was never on the recall list, the window starts when it entered service.
- Find every use. Search inspection records, travelers, the instrument's use log and CMM programs for every lot and characteristic it measured in the window. Where records name no instrument, count every instrument that could have been used.
- Screen. For each lot, correct the extreme readings by the largest error, in the direction that matters. A lot whose readings sit further from the limit than the error cannot hold a bad piece.
- Refine. For lots still in question, use the error at the size actually measured, from the certificate or the lab. It is often smaller.
- Act on what remains. Re-measure stock and work in process with another instrument; for shipped product in question, tell the customer with the data and agree the disposition.
- Fix the instrument and the system. Adjust or retire it, change the interval, check similar instruments, and fix whatever made the trace slow.
- Close with the evidence when every lot is decided, the decision has a name, and the customer has been told where needed. Log it on the OOT log and the register.
Direction matters
| The instrument ... | So the true values are ... | And the limit at risk is ... |
|---|---|---|
| reads high (shows more than the true value) | lower than recorded | the lower limit |
| reads low (shows less than the true value) | higher than recorded | the upper limit |
| error in both directions, or not known | either side of the reading | both limits |
| go plug worn small | bores it passed may be smaller than allowed | the lower limit of the bore |
| go ring worn large | shafts it passed may be larger than allowed | the upper limit of the shaft |
Telling the customer
When product in question has shipped, the customer is told, with the lots, the readings, the worst case and what you propose. Your customers' requirements set how fast and in what form; many expect notification within days of the finding, not at the end of the assessment. Notify early and refine afterward: a customer who hears about a possible problem quickly, with data, usually makes a quick decision.
What the first notification says, in this order. Keep it to one page and attach the data.
A record to fill in: what to write in each field
| What happened | The instrument, the date it was found out of tolerance, the as-found error and its direction, and the last known good date. |
|---|---|
| Your product in question | Part numbers, lots, quantities, ship dates and your purchase order numbers; the characteristic and its limits. |
| What we know so far | The readings, the worst case beyond the limit, and what has been cleared and how. |
| What we have done | Instrument quarantined or corrected; stock and work in process re-measured or held; our nonconformance reference. |
| What we propose and need from you | The disposition we propose, any parts we ask you to hold or return, and the date of our next update. |
| Contact | One named person, with phone and email. |
The Word and fillable PDF handbook give you this as a form with space to write.
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A management aid, not certification or a registrar audit. Using it does not by itself show conformity to AS9100D or any other standard, and your customers' requirements may add to it.
Clause numbers refer to AS9100D (SAE AS9100 Rev D) unless another document is named. The standards' text is not reproduced here: use your own licensed copy.
Aegis Insights are our own guidance, labeled wherever they appear: how we approach this work, not a requirement of any standard or customer.