FAT vs SAT for Industrial Machinery: Acceptance Testing Guide

Short answer

Quick Answer

FAT (factory acceptance test) proves the equipment works at the supplier's factory before shipment. SAT (site acceptance test) proves it works in your plant, with your utilities, materials and operators. Both should be defined in the RFQ with measurable criteria.

What does a factory acceptance test check?

FAT is the last chance to find problems cheaply, before crating and shipping.

Mechanical build and documentation against the specification
Control logic, safety functions and alarms
Dry runs or test runs with representative material where possible
Agreed punch list before release for shipment

What does a site acceptance test check?

SAT confirms installed performance: output rate, quality, utility consumption and integration with upstream and downstream equipment, measured under conditions agreed in advance.

What should the RFQ say about acceptance?

Test location, duration and who attends
Measurable criteria: output, reject rate, uptime, consumption
Materials the buyer must supply for testing
Link between acceptance milestones and payment
Remedies if criteria are not met

Quick questions

Is FAT always required?+

It is strongly recommended for custom or high-value equipment. For standard catalogue items, a documented test report may be sufficient.

Who pays for FAT travel?+

It is negotiable. State it in the RFQ so all suppliers quote on the same basis.

Can payments be tied to FAT and SAT?+

Yes. Many contracts link a payment milestone to successful FAT and the final milestone to SAT sign-off.

Summary

FAT proves the machine at the factory; SAT proves it in your plant
Define measurable acceptance criteria in the RFQ
Link milestones and remedies to test results

Global B2B Group is an independent, human-reviewed procurement channel — not a manufacturer, contractor or lender. Figures and methods here are general guidance; confirm project-specific details with qualified advisers.

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