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Control Chart Template

Appendix number: 11-App-02
Parent procedure: Procedure 11 — Quality Assurance

Instructions

Maintain one control chart per QC parameter (e.g., CRM recovery for each analyte, CVS recovery, blank level, duplicate RPD). Plot each QC result sequentially as it is obtained. Apply the interpretation rules in Procedure 11, Section 6.4.3 after each new data point. Review and recalculate limits at least annually.

Chart Identification

FieldEntry
Method / SOP[e.g., SOP-10-001 — ICP-OES multi-element analysis]
QC parameter[e.g., CRM Ni recovery (%)]
CRM / standard identification[e.g., NIST SRM xxxx, lot yyyy]
Chart started[Date]
Limits calculated from[e.g., Data points 1–20, collected DD/MM/YYYY – DD/MM/YYYY]

Control Limits

StatisticValue
Centre line (mean)[e.g., 99.3%]
Standard deviation (σ)[e.g., 1.2%]
Upper warning limit (+2σ)[e.g., 101.7%]
Lower warning limit (−2σ)[e.g., 96.9%]
Upper action limit (+3σ)[e.g., 102.9%]
Lower action limit (−3σ)[e.g., 95.7%]

Data Log

EntryDateRun IDAnalystResultWithin limits?Rule violation?Notes / action
1[Date][ID][Initials][Value][Y/N][None / rule violated]
2
3
...

Limit Recalculation Log

DateReason for recalculationData points usedNew meanNew σNew limitsApproved by
[Date][e.g., Annual review / new CRM lot / instrument change][e.g., Points 21–40][Value][Value][UWL/LWL/UAL/LAL][Technical Manager]

Notes

[Record any observations about the chart — e.g., "Data points 15–18 showed an upward trend; investigated and traced to gradual degradation of peristaltic pump tubing. Tubing replaced after point 18; subsequent results returned to centre line."]