Flow-weighted compliance verdict
The headline verdict accounts for how the meter actually operates across the year — not just at the design point. If the flow-weighted uncertainty exceeds the framework limit, the report says so upfront.
Laboratory density flow-bias
Where lab samples are provided, the report quantifies the systematic measurement bias — how much the meter is over- or under-reading — separate from the random uncertainty.
Detailed uncertainty budget
Each contributor shown with source, sensitivity coefficient, standard uncertainty, variance share, degrees of freedom, and Type A or Type B treatment per ISO 5168.
Calculation workings (Appendix A)
Step-by-step derivation for every budget row: raw input → unit conversion → standard uncertainty → sensitivity coefficient → contribution. ISO clause citations throughout.
Complete input record (Appendix B)
Every user-supplied value exactly as entered, grouped by calculator step. Excluded inputs listed with the engineer's documented justification for each exclusion.
Instrument register (Appendix C)
Make, model, serial number, calibration certificate, and PM references for each instrument in the metering loop — DP transmitter, pressure, temperature, densitometer, plate, flow computer, and lab equipment.
Flow profile back-test (Appendix D)
Back-tests the uncertainty at each day's average flow from the past year, producing a flow-weighted mean uncertainty, percentiles, distribution histogram, and worst-day analysis.
Turndown curve
Charts the expanded uncertainty from 5% to 120% of design flow, showing where ΔP errors amplify at turndown and where the compliance threshold is crossed.
Audit trail & traceability
Site, tag, service, engineer, document reference, framework, calculation date, input fingerprint hash, report serial number, and online verification URL.
