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TNI Standards Guidance

Disclaimer: This material represents the opinion of its authors. It is intended solely as guidance and does not include any mandatory requirements except where such requirements are referenced. This guidance does not establish expectations of being implemented universally, exclusively, in whole, or in part.

This guidance does not establish or affect legal rights or obligations and is not finally determinative of the issues it addresses. It does not create any rights enforceable by any party in litigation with TNI, its accreditation bodies, or affiliated institutions. Any decisions made by TNI regarding requirements addressed in this guidance will be made by applying the applicable standards, policies or procedures to the relevant facts.


Module: Quality Systems

Subject: LIMS Time Stamp Error

Question 1

You notice that the computer time stamp on raw data is off by one hour. What now?

Investigate backwards in time to establish when the error began on the raw data.  Determine how the time stamp is generated (e.g., does it originate with IT or sample receiving, and which computer(s) are affected.  Does it affect all records (i.e. those uploaded from analytical instruments with embedded time stamp and those generated by manual entry)?  Examine maintenance records, particularly for computer upgrades for daylight savings time and signs of human involvement or improper practice.

Involve Analyst(s), IT personnel, and QA officer, possibly extending to the client, the lab’s technical director and even the instrument manufacturer, depending on investigation’s results.  Assess the severity of the investigation results and notify, as appropriate, any affected client(s), lab personnel, HR (if improper practice), the AB (if PTs are affected), the PT provider, department heads, communications personnel, and risk management personnel.

Follow-Up Action:  Correct the time, investigate data sets to see if holding times are exceeded or other time-sensitive records are impacted, revise and re-issue affected reports.  Review relevant SOPs to see if amendments are needed.   Retrain personnel responsible for the error and investigate/verify the effectiveness of personnel retraining.


2009 & 2016 TNI

2009 TNI V1M2 and 2016 TNI Rev. 2.1 V1M2

4.0 Management Requirements, §4.1.5 a, f, g, & h
4.2 Management, §4.2.1 Laboratories shall maintain SOPs that accurately reflect all phases of current laboratory activities, such as assessing data integrity,

4.3 Document Control (ISO/IEC 17025:2005, Clause 4.3), §

4.9 Control of Nonconforming Environmental Testing Work (ISO/IEC 17025:2005(E), Clause 4.9), §4.9.1 a thru e, and 4.9.2

4.11 Corrective Action (ISO/IEC 17025:2005(E), Clause 4.11), §4.11.1 thru 4.11.5

4.13 Control of Records, § and

4.13.3 Additional Requirements

a) The laboratory shall establish a record keeping system that allows the history of the sample and associated data to be readily understood through the documentation. This system shall produce unequivocal, accurate records that document all laboratory activities such as laboratory facilities, equipment, analytical methods, and related laboratory activities, such as sample receipt, sample preparation, or data verification, and inter-laboratory transfers of samples and/or extracts.

f) All information necessary for the historical reconstruction of data shall be maintained by the laboratory.

v. time of analysis is required if the holding time is seventy-two (72) hours or less, or when time critical steps are included in the analysis (e.g., extractions and incubations);

5.2 Personnel (ISO/IEC 17025:2005, Clause 5.2), §5.2.1

5.10 Reporting the Results, §5.10.9