LAB-QM-ANA-006 — Calibration and Verification of Ancillary Measuring Devices and Labware Policy

1.0 Purpose

The purpose of this policy is to establish defined procedures for the calibration, periodic verification, maintenance, and cleaning of ancillary measuring devices and laboratory glassware at Tarangnan Community Hospital Clinical Laboratory. This ensures volumetric accuracy, temperature precision, timing fidelity, and residue-free labware across all analytical testing procedures.

2.0 Scope

This policy applies to all mechanical pipettes, laboratory thermometers, digital timers, centrifuges, and reusable laboratory glassware across all sections of the Clinical Laboratory, governing all Medical Technologists and Laboratory Aides.

3.0 Definitions

• Critical Ancillary Equipment — secondary measuring devices (pipettes, thermometers, timers, centrifuges) whose measurement accuracy directly impacts examination trueness.
• Traceability — property of a measurement result whereby the result can be related to a reference through a documented unbroken chain of calibrations.
• Certified Reference Thermometer — a standardized thermometer calibrated by an accredited national metrology body (NIST or equivalent) used solely to calibrate in-use thermometers.
• Reference Timer — an electronic time standard used to verify the accuracy of routine mechanical and digital laboratory stopwatches.
• Glassware Neutrality — absence of acidic or alkaline detergent residues on washed labware, verified by neutral pH indicator testing.

4.0 Responsibility

4.1 Hospital Director

• Approves institutional service contracts with accredited calibration laboratories for external calibration of reference standards.
• Exercises executive oversight per Organization and Governance.

4.2 Pathologist

• Reviews and authorizes annual calibration summaries and corrective action plans for failed ancillary measuring devices.
• Exercises clinical oversight per Organization and Governance.

4.3 Chief Medical Technologist / Laboratory Quality Manager

• Maintains the master calibration schedule and tracking registry for all pipettes, thermometers, timers, and centrifuges.
• Conducts or supervises in-house verification checks and coordinates the shipment of reference standards to accredited external metrology facilities.
• Quarantines out-of-tolerance devices and ensures effective detergent residue testing on cleaned labware batches.

4.4 Contracted Calibration Laboratory (External / Accredited Metrology Provider)

• Performs annual certified calibration of reference thermometers and tachometers against traceable national standards.
• Issues formal calibration certificates detailing measurement uncertainty.

4.5 Medical Technologists

• Inspect ancillary devices before use, verify calibration status tags, and perform quarterly volumetric checks on micropipettes.
• Verify timer accuracy and centrifuge operating speeds at defined intervals.
• Tag and remove from service any pipette, thermometer, or timer exhibiting physical damage or measurement error.

4.6 Laboratory Aides

• Clean and decontaminate reusable glassware strictly following established washing and neutralization procedures.
• Perform and record pH indicator checks for detergent residue on washed glassware batches under Medical Technologist direction.
• Shall never perform pipette volume adjustments, balance calibrations, or tachometer verifications.

5.0 Policy / Procedure

5.1 Policy Statement

The laboratory shall calibrate or verify all ancillary measuring devices affecting diagnostic examination quality before initial use and at scheduled intervals thereafter. Equipment calibration shall establish metrological traceability to certified national or international standards. Glassware shall be maintained clean, non-leaching, and chemically neutral to prevent sample contamination.

5.2 General Calibration and Verification Requirements

• Every critical ancillary device shall be marked with an identification code and a current calibration status label indicating calibration date, due date, and initials of the verifier.
• Calibration and verification frequencies:

5.3 Pipette Calibration and Maintenance

• Pipettes shall be inspected for barrel integrity, plunger smoothness, and tip fit prior to routine use.
• Semi-annual gravimetric calibration shall be performed by dispensing 10 replicates of deionized water at minimum, mid-range, and maximum volume settings.
• If accuracy or precision falls outside acceptable tolerances, the pipette shall be cleaned, seal or O-ring replaced, recalibrated, or returned to the vendor.

5.4 Thermometer Calibration and Verification

• A designated certified reference thermometer with current calibration certification shall be maintained and stored safely to serve as the calibration standard.
• In-use spirit-in-glass and digital probe thermometers shall be calibrated against the reference thermometer at three bath temperatures (ice bath 0 °C, ambient 20 °C to 25 °C, and incubator 37 °C).
• Any thermometer exhibiting liquid column separation, air bubbles, or error exceeding ±1.0 °C shall be discarded immediately.

5.5 Timer and Stopwatch Verification

• Digital timers and instrument interval clocks shall be checked semi-annually across test intervals (1 minute, 5 minutes, 15 minutes, and 30 minutes).
• Timers showing variance greater than ±1 second per 10 minutes shall be adjusted, fitted with fresh batteries, or replaced.

5.6 Centrifuge Inspection and Speed Verification

• Centrifuge bowls, buckets, and trunnions shall be cleaned and disinfected weekly.
• Operating rotational speed (RPM) shall be verified annually across routine clinical speeds (e.g., 3,000 to 4,000 RPM) using a calibrated optical tachometer.
• Centrifuges exhibiting abnormal vibration, excess noise, or speed deviation >2% shall be removed from service.

5.7 Glassware Washing, Storage, and Neutrality Testing

• Reusable glassware shall be washed using phosphate-free, residue-free laboratory detergent.
• Washing sequence: - Primary rinse with tap water immediately after use; - Soak and wash in warm laboratory detergent solution; - Rinse thoroughly with tap water at least 3 times; - Final thorough rinse with Type 3 distilled water.
• Detergent residue check: One piece from each washed batch shall be tested by adding 2 to 3 drops of 0.04% bromothymol blue indicator solution. The solution must remain neutral green (pH 6.5 to 7.5). A blue color (alkaline) or yellow color (acid) indicates inadequate rinsing; the entire batch shall be re-rinsed.
• Clean glassware shall be inverted on drying racks and stored in closed cabinets protected from dust.

5.8 Out-of-Tolerance Action and Remediation

• Any device failing verification or calibration tolerances shall be labeled with a Red OUT OF SERVICE tag and removed from workstations.
• The Chief Medical Technologist shall evaluate whether previous patient results generated using the compromised device were adversely affected, logging actions in accordance with Occurrence Management Policy.

6.0 Records

The following controlled record is maintained under this policy:

All calibration certificates, raw calibration data sheets, tachometer reports, and glassware pH logs shall be retained in accordance with Laboratory Retention Schedule Policy.

These records are maintained electronically in analyzer memory, the LIS, and dedicated electronic workbooks registered under F-QM-002-B-V0 (Decision D5); no separate paper form is maintained for them.

7.0 References

• DOH QMS Tool, Section 2 (Resource Management — Equipment & Instruments)
• DOH Administrative Order No. 2021-0037, Annex B1 (Technical Standards for Clinical Laboratories)
• ISO 15189:2022, Clause 6.5 "Equipment calibration and metrological traceability"
• WHO LQMS Handbook, Chapter 3 "Equipment"
• CLSI GP31-A, Laboratory Instrument Implementation, Verification and Maintenance

Companion policies:

• Equipment Temperature Monitoring Policy — Equipment management and environmental temperature monitoring
• Reagent Management Policy — Reagent and laboratory water quality management
• Laboratory Retention Schedule Policy — Retention schedules for calibration records and device maintenance logs