P20.2
Equipment Calibration Schedule
Procedure 31 of 40 · Chapter 20 · §20.2.3
1 table 0 notes
Table 1
| Instrument | Calibration Item | Frequency | Reference Standard | Acceptance Criteria | Action on Failure |
|---|---|---|---|---|---|
| Analytical balance | Mass, linearity, eccentricity | Annual (ext.); Monthly (int.) | F1/E2 certified weights, 1 mg–200 g | ±0.1 mg at 20 g; ±0.5 mg at 200 g | Remove from service; tag “Out of Calibration”; service |
| pH meter | Slope, offset, asymmetry | Daily (before use); Annual (ext.) | NIST buffers: pH 4.01, 7.00, 10.01 | Slope 95–102%; offset < ±30 mV | Replace electrode if slope < 90%; re-qualify |
| Brookfield viscometer | Torque, spring constant | Quarterly (int.); Annual (ext.) | Silicone standard, 1,000 cP ± 1% at 25 °C | Within ±2% of certified value | Recalibrate; replace spring if deviation > 5% |
| Autotitrator | Burette volume, electrode response | Monthly (int.); Annual (ext.) | Certified volumetric flask; 0.004 M SDS | Burette ±0.3%; RSD < 0.5% | Reprime burette; recondition electrode |
| Digital density meter | Frequency vs. density | Daily (ver.); Quarterly (int.) | Air + distilled water at 25 °C | ±0.0001 g/cm³ vs. certified water | Dry U-tube; recalibrate; check for bubbles |
| UV-Vis spectrophotometer | Wavelength, photometric accuracy | Quarterly (int.); Annual (ext.) | Holmium oxide filter; neutral density CRM | Wavelength ±1.0 nm; Photometric ±0.010 A | Replace lamp; clean optics |
| Thermometer | Temperature indication | Annual (external) | Ice point + reference thermometer | ±0.2 °C over range | Recalibrate or replace |
| Karl Fischer titrator | Water equivalent | Weekly | Disodium tartrate dihydrate (15.66% water) | Water equivalent ±3% of nominal | Replace desiccant; fresh reagent |