Proficiency Testing Record

Appendix number: 11-App-04
Parent procedure: Procedure 11 — Quality Assurance

Instructions

Complete one record per PT round per method. For satisfactory results, complete Sections A and B. For questionable or unsatisfactory results, also complete Section C. File in quality records and reference in the PT/ILC schedule (Appendix 11-App-03).

---

Section A — PT Round Details

Field	Entry
PT record number	[e.g., PT-2025-003]
Method / SOP	[e.g., SOP-10-001 — ICP-OES multi-element analysis]
PT provider	[e.g., GeoPT / LGC / other]
Scheme name and round	[e.g., GeoPT Round 52]
Measurand(s)	[e.g., Ni, Co, Mn, Li, Al, Fe in silicate matrix]
Sample identification	[e.g., GeoPT52-A, received DD/MM/YYYY]
Date of analysis	[Date]
Analyst	[Name]
Equipment used	[e.g., ICP-OES-001]
Sample treated as routine?	[Yes / No — if No, explain]

Section B — Results and Evaluation

Measurand	Laboratory result	Unit	Assigned value	Uncertainty of assigned value	z-score (or other statistic)	Classification
[e.g., Ni]	[Value]	[e.g., % w/w]	[Value]	[Value]	[e.g., 0.8]	[Satisfactory]
[e.g., Co]
[e.g., Mn]
[e.g., Li]
[e.g., Al]
[e.g., Fe]

Overall assessment: [All satisfactory / One or more questionable / One or more unsatisfactory]

Evaluated by: [Technical Manager, date]

---

Section C — Investigation of Questionable or Unsatisfactory Results

Complete this section for any measurand with |z| > 2.0 or equivalent.

C.1 — Initial checks

Check	Outcome
Transcription / calculation error	[Checked — no error found / error found: describe]
Correct sample analysed	[Confirmed / mismatch found: describe]
Method followed as documented	[Confirmed / deviation found: describe]
IQC data from same period normal	[CRM recovery, CVS, blanks reviewed — all satisfactory / anomalies found: describe]

C.2 — Root cause investigation

Area investigated	Findings
Sample preparation	[e.g., Digestion reviewed — no issues / incomplete dissolution suspected]
Calibration / standards	[e.g., Calibration standards checked against independent source — no discrepancy / discrepancy found]
Instrument performance	[e.g., Instrument logs reviewed — no maintenance issues / drift detected in period]
Analyst technique	[e.g., Analyst interviewed — procedure followed correctly / procedural variation identified]
Environmental conditions	[e.g., Temperature/humidity logs reviewed — within specification / excursion on date X]
Matrix effects	[e.g., PT sample matrix differs significantly from routine samples — possible interference]
Other	[Any additional factors considered]

Identified root cause: [Describe the root cause, or state "no assignable cause identified" with justification]

C.3 — Impact assessment

Question	Response
Could customer results from the same period be affected?	[Yes — identify affected reports / No — explain why]
Number of potentially affected reports	[n]
Customer notification required?	[Yes — per Procedure 14 / No — explain]
Retained PT sample re-analysed?	[Yes — result: [value], z-score: [value] / No — explain / not available]

C.4 — Corrective action

Field	Entry
Corrective action taken	[Describe the action — e.g., "Calibration standards remade from new stock; instrument recalibrated; CRM re-analysed with satisfactory recovery."]
CAR number (if raised)	[e.g., CAR-2025-012, per Procedure 14]
Effectiveness verification	[Describe how effectiveness was confirmed — e.g., "Next 10 routine CRM recoveries all within ±2σ of control chart mean." or "Satisfactory result in subsequent PT round."]
Date closed	[Date]

Investigation completed by: [Technical Manager, date]
Reviewed by: [Quality Manager, date]