Help Center

Still have a problem? Technical Support

OOS

For more information about OOS, enter a question into the box above, or select from one of the questions below. You can select a different product from the list in the left hand panel.

Q:	What kind of transient equipment malfunction can occur in HPLC and how can it be resolved? A: An auto-injector could inject bubbles during an operation; therefore, repeated re-injections will provide strong evidence that the problem can be attributed to the instrument, rather than the sample or its preparation.
Q:	What kind of transient equipment malfunction can occur in LAL-endotoxin kinetic testing and how can it be resolved?
Q:	Why do I need to conduct an investigation if an OOS test result is obtained?
Q:	What is the purpose of an OOS investigation?
Q:	Who should investigate OOS?
Q:	Which parts of the CGMP regulations apply to laboratory operations?
Q:	Which section of the CGMP regulations specifies that products failing to meet established standards and other relevant quality control criteria will be rejected?
Q:	How do I handle an OOT result?
Q:	Can I ignore an OOS investigation if the rejection of a batch is based on an OOS result?
Q:	Why is it necessary to carry out an OOS investigation if the rejection of a batch is based on an OOS result?
Q:	Which sections of the CGMP regulations require that written records of the investigation are made, including conclusions of the investigation and follow-up?
Q:	How do I carry out a meaningful OOS investigation?
Q:	What should the analyst do, whenever possible, before discarding the test solution?
Q:	When do I need to conduct a complete failure investigation?
Q:	Who is responsible for the first course of action?
Q:	Who has the primary responsibility for ensuring accurate laboratory test results?
Q:	Which section of the CGMP regulations requires that the analyst should ensure that only those instruments meeting established specifications are used?
Q:	Which section of the CGMP regulations requires that the analyst should ensure that only properly calibrated instruments are used?
Q:	What is the usual time requirement during the LAL-endotoxin kinetic determination?
Q:	What should the analyst do during the testing process?
Q:	What system suitability requirements may be considered?
Q:	Why could the optical density change calculation method generate OOS results?
Q:	If signal drift is a problem, then which LAL-endotoxin kinetic curves are most likely to be affected?
Q:	What should be done in the case of obvious errors?
Q:	What should be done with OOS results if clear evidence of laboratory error exists?
Q:	What should be done if unexpected results are obtained and no obvious explanation exists?
Q:	Can you list some of the obvious errors that could invalidate results?
Q:	Is it a good idea to continue with an analysis to see what results can be obtained when an obvious error is known, and that the analysis will be invalidated at a later time for an assignable cause?
Q:	What should the supervisor's responsibilities be in the case of OOS results?
Q:	What should be included in the re-examination of an immediate assessment?
Q:	How frequently is it reasonable to experience a lab error?
Q:	How should I select the procedure for an OOS failure investigation?
Q:	Who should conduct an investigation and what departments should be included?
Q:	Who should do the retesting?
Q:	What steps should be taken during the supervisor's assessment?
Q:	What should be done with OOS results when evidence of laboratory error remains unclear?
Q:	How many times can I repeat the retests?
Q:	If varying test results are obtained, and when the evidence of laboratory error remains unclear, then what may be the cause of the OOS problem?
Q:	What practices are used in the laboratory phase of an OOS investigation?
Q:	What conditions indicate retesting?
Q:	Which section of the CGMP regulations requires the establishment of specifications, standards, sampling plans, test procedures, and other laboratory control mechanisms?
Q:	What should be done if test results obtained after the predetermined number of retests are still unsatisfactory?
Q:	If I have 2 results, one original OOS result, and one of the retest results which one should be included in the batch?
Q:	How should I document my retest results?
Q:	Can you give examples when averaging can be used?
Q:	Can you give examples when averaging cannot be used?
Q:	What conditions are required for the use of averaging?
Q:	How does resampling differ from retesting?
Q:	Based on the above problems, can I use a new sampling method?
Q:	When is resampling of the batch indicated?
Q:	Do the CGMP regulations require that the acceptance and/or rejection levels be based on statistically valid quality control criteria?
Q:	How can an outlier point generate OOS results for LAL-endotoxin testing?
Q:	What determines validity for the averaging of test data?
Q:	What corrective action can you take in case of outliers?