Monitoring and Compliance · Online Instruments
How Are Online Analyzers Calibrated and Verified?
Calibration adjusts or establishes the relationship between instrument response and known references. Verification challenges that relationship without automatically changing it. The terms should not be treated as interchangeable.
Use references accepted by the method, regulator, and manufacturer. Confirm identity, value, lot, expiration, storage, preparation, and temperature requirements. Standards that are contaminated or outside their usable period cannot validate an instrument.
Record the as-found condition before adjustment, then the work performed and as-left condition. The as-found result helps determine whether earlier process data may have been affected.
If acceptance criteria are not met, place the instrument in the appropriate status, notify responsible staff, assess affected data, and use authorized backup monitoring. Repeated adjustment without finding the cause can conceal deterioration.
Key point: Verification tests performance; calibration establishes or adjusts response, and the as-found condition protects the history of earlier data.
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Water Treatment Part 3: Monitoring, Control and Compliance
This page comes from the course. It covers sampling, plant lab tests, online instruments, chemical feed math, process control, storage and distribution handoff, drinking water rules and records, and emergencies, one step at a time, with short knowledge checks and a certificate of completion.
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