The FGIS Equipment Handbook states in part that to ensure the accuracy and integrity of official inspections, sampling and inspection equipment used for official purposes must be:
- of an FGIS-approved model and type (xls),
- properly installed and aligned,
- kept in good repair,
- periodically tested, and
- protected from unauthorized adjustments.
Inspection equipment that doesn't meet these requirements is not approved for official use and is removed from service until subsequent testing establishes its accuracy.
Periodic testing of official inspection equipment enables the testing office to:
- Evaluate the performance of a piece of equipment against the "Standard" equipment;
- Determine the need for any repairs or re-calibration of the equipment;
- Interpret any mechanical and/or physical trends in the equipment's performance;
- Establish documentary proof of accuracy through completion of official checktest forms;
- Instill confidence in the accuracy of the equipment;
- Comply with the provisions of the United States Grain Standards Act (USGSA).
Some equipment is tested "in-house" in FGIS and official agency labs by direct comparison with standard reference weights or Standard equipment. Other equipment is tested by the exchange of checktest samples sent to the field office from Technology and Science Division -- or to the official agency from the field office. All FGIS and agency inspection personnel use the same equipment testing procedures, which are found in the FGIS Equipment Handbook and the FGIS Moisture Handbook.