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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: Results Do Not Match Historical Values

Question 1

Your client says recently reported results do not match historical values. During your investigation, you determine the analyst has incorrectly entered the initial volume as 100mL instead of 1000mL. What do you do to make this right?

Verify, using internal audit techniques, the true volume through traceability of sample/standard.  If the volume was 1000 mL, determine how the error was made.  Are there other instances of a reported 100 mL final volume, and establish the impact of this error.   Determine whether secondary review procedures should have found the mistake.  Was a second level review actually performed, and if so, what was the mechanism?  How was the volume measured?

Depending on the results of the investigation, and as appropriate, involve the QA manager, analyst, supervisor and client-facing staff.  Notify the analyst, QA, supervisor, manager, potentially HR, the legal department and the lab director.  Notify the client(s) of results, and depending on investigation, notify the AB and regulatory body.

Follow-Up Action:  After Investigation, determine the root cause and perform corrective action (SOP revision, employee training, and potential disciplinary action depending on analyst’s involvement.  Issue revised report to client(s).  Evaluate corrective action and review client complaint procedures.  Audit the test method and other results that might have been susceptible to the same error.  Revise processes as necessary.


2009 TNI V1M2 and 2016 TNI Rev. 2.1 V1M2

4.0 Management Requirements, §4.1.5 a, b, f, g & h

4.2 Management, §4.2.1 The quality manual shall contain or reference:

l) procedures to be followed for feedback and corrective action whenever testing discrepancies are detected, or departures from documented policies and procedures occur;

n) procedures for dealing with complaints;

q) procedures for establishing that personnel are adequately experienced in the duties they are expected to carry out and are receiving any needed training; and Laboratories shall maintain SOPs that accurately reflect all phases of current laboratory activities, such as assessing data integrity, corrective actions, handling customer complaints, and all methods.

4.8 Complaints (ISO/IEC 17025:2005(E), Clause 4.8)

The laboratory shall have a policy and procedure for the resolution of complaints received from customers or other parties. Records shall be maintained of all complaints and of the investigations and corrective actions taken by the laboratory (see also 4.11).

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

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

4.11.6 The laboratory shall have documented procedure(s) to address Sections 4.11.1 and 4.11.3 through 4.11.5. These procedure(s) shall also include:

a) which individual(s) or positions are responsible for assessing each QC data type; and

b) which individual(s) or positions are responsible for initiating and/or recommending corrective actions.

4.13 Control of Records, §

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

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

5.10 Reporting the Results, §5.10.9