How do you design a tank farm inventory measurement system with custody transfer accuracy?

Custody transfer tank gauging design: Select gauging technology (servo gauge for highest accuracy +/-0.5mm, radar for general use +/-1mm), integrate temperature measurement (multi-spot average for stratification), density measurement (in-tank densitometer or spot sampling), and water bottom detection. Implement tank strapping tables (volumetric calibration), temperature compensation to standard conditions (API 11.1), and free water measurement. Data acquisition system with inventory management software calculates gross and net volumes, handles product transfers, and provides audit trail. Address roof position correction (floating roof), heel volume calculation, and alarm management. Certify complete system to OIML R85 or API MPMS Chapter 3.