Key takeaways
- A Factory Acceptance Test (FAT) confirms that equipment meets specifications at the vendor’s facility before shipment to the client site.
- A Site Acceptance Test (SAT) confirms that equipment installs correctly and integrates with site utilities, systems, and peripherals in its working environment.
- FAT and SAT are both required in GxP-regulated equipment lifecycles for pharmaceutical, biotech, and medical device manufacturers.
- A thorough FAT reduces on-site remediation during SAT, and a thorough SAT generates baseline evidence that streamlines installation qualification (IQ) and operational qualification (OQ) execution.
- Kneat Gx enables validation and engineering teams to execute FAT and SAT protocols digitally, capturing test evidence, managing deviations, and generating audit-ready documentation in a single platform.
For manufacturers operating under GxP regulations, Factory Acceptance Tests (FAT) and Site Acceptance Tests (SAT) are sequential checkpoints that bridge equipment procurement and formal qualification. FAT confirms equipment meets specifications before it leaves the vendor; SAT confirms it functions correctly once installed on site. If done well, both reduce the scope of remediation required during IQ, OQ, and PQ.
Any project involving third-party equipment should incorporate both into the system lifecycle.
FAT vs. SAT at a glance
| Dimension | FAT | SAT |
|---|---|---|
| Full name | Factory Acceptance Test | Site Acceptance Test |
| Purpose | Confirm equipment meets specifications before shipment | Confirm equipment installs and integrates correctly on site |
| Location | Vendor’s manufacturing facility | Client’s manufacturing site |
| Timing | Before shipment | After installation, before IQ |
| Responsible party | Vendor executes; client witnesses and approves | Client executes; vendor may support |
| Key outputs | Signed FAT protocol, punch list, as-built drawings, calibration certificates | Signed SAT protocol, punch list, utility verification records, interlock confirmation, operator training records |
| Regulatory context | ISPE Baseline® Guide, GAMP 5, EU GMP Annex 15 | ISPE Baseline® Guide, GAMP 5, EU GMP Annex 15 |
What is a FAT?
A Factory Acceptance Test is performed at the vendor’s facility before shipment. The vendor tests the system against the client’s approved test plans and specifications to confirm readiness for installation.
The ISPE Baseline® Guide for Biopharmaceutical Manufacturing Facilities defines FAT as “the partial commissioning and qualification of equipment and/or systems prior to their shipment from the fabricator’s site.” GAMP 5 (Second Edition, 2022) defines it as “an Acceptance Test in the Supplier’s factory, usually involving the Customer.”
FAT acceptance checklist
On acceptance of a FAT, verify the following. Missing items here are the most common cause of delays during SAT and IQ.
- Executed FAT protocol, signed and dated
- Maintenance and user manuals
- Recommended spare parts list
- Certificate of compliance
- As-built technical drawings (electrical, mechanical, pneumatic, and process)
- Materials certificates and data sheets for product-contact components
- Main equipment data sheets
- Instrument calibration certificates traceable to national standards
- Welding process qualification records for product-contact welds
What is a SAT?
A Site Acceptance Test is performed at the client’s site after installation. It confirms the system interfaces correctly with site utilities, adjacent systems, and peripherals in its working environment.
The ISPE Commissioning and Qualification Baseline® Guide defines SAT as “inspection and/or dynamic testing of the systems or major system components to support the qualification of an equipment system conducted and documented at the manufacturing site.”
SAT execution checklist
When performing a SAT, verify the following. Each item supports the evidence base for IQ.
- Finishing visual check for shipping damage and installation condition
- Main components match the as-built drawings from FAT
- Internal box pressure and ventilation settings meet site conditions
- Site utilities (compressed air, purified water, electrical supply) meet FAT-validated specifications
- Mechanical and software interlocks operate as specified
- Safety device responses documented against the approved test plan
- Operator training completed and recorded before IQ
Where FAT and SAT fit in the qualification lifecycle
FAT and SAT are commissioning activities that generate evidence supporting qualification — they do not replace IQ, OQ, or PQ. The standard lifecycle runs:
URS → DQ → vendor selection → FAT → shipping and installation → SAT → IQ → OQ → PQ
A thorough FAT reduces deficiencies found during SAT. A thorough SAT reduces deficiencies found during IQ. Invest upstream and the whole qualification timeline compresses.
What documentation do FAT and SAT require?
FAT and SAT each require a pre-approved protocol, an executed test record, a punch list, and a formal sign-off package. These documents form part of the equipment’s qualification dossier and must be available for regulatory inspection.
FAT documentation requirements
- FAT protocol — authored and approved before testing begins; specifies test cases, acceptance criteria, and responsible parties. Completed during testing with contemporaneous entries, electronic signatures, and attached evidence
- FAT punch list — documents open items, deviations, and agreed remediation actions
- FAT sign-off package — includes the executed protocol, punch list closure records, and all deliverables listed in the FAT acceptance checklist above
SAT documentation requirements
- SAT protocol — authored and approved before testing begins; references the URS and FAT outcomes. Completed during testing with contemporaneous entries and attached evidence
- SAT deviation log — documents any test failures, their root causes, and corrective actions
- SAT punch list — documents open items, deviations, and agreed remediation actions
- SAT sign-off package — includes the executed protocol, deviation log, and utility verification records
- Traceability matrix — links each SAT test case back to the corresponding URS requirement
Traceability between the URS, FAT, and SAT is a regulatory expectation under EU GMP Annex 15 and the ISPE Commissioning and Qualification Baseline® Guide. Gaps in traceability are a common observation during health authority inspections.
Typical FAT and SAT test cases for regulated manufacturing equipment
FAT and SAT test cases for GxP-regulated equipment cover functional verification, safety system confirmation, and utility interface testing. The specific test cases depend on the equipment type, but the categories below apply across most pharmaceutical, biotech, and medical device manufacturing environments.
Common FAT test cases
- Alarm verification — trigger each alarm condition and confirm the system responds correctly; document the alarm setpoint, the trigger method, and the observed response
- Control system functional testing — verify that the human-machine interface (HMI) operates as specified; confirm software version and configuration match the approved design
- Instrument calibration verification — confirm that all instruments carry current calibration certificates before testing begins
- Utility simulation testing — simulate site utility conditions (compressed air pressure, electrical supply voltage) to confirm the equipment operates within specification under realistic conditions
- Interlock testing — verify that all safety interlocks activate correctly under fault conditions
- Cleaning-in-place (CIP) and sterilization-in-place (SIP) cycle verification — for applicable equipment, confirm cycle parameters meet the validated specification
Common SAT test cases
- Utility hookup confirmation — verify that site utilities connect correctly and deliver the specified parameters (pressure, flow rate, temperature, electrical supply)
- Integration testing — confirm the equipment communicates correctly with connected systems (building management systems, data historians, manufacturing execution systems)
- Interlock testing under site conditions — repeat FAT interlock tests under actual site conditions to confirm no environmental or utility factors affect interlock performance
- Safety device verification — confirm all safety devices (pressure relief valves, emergency stops, door interlocks) function correctly in the installed configuration
- Environmental condition verification — confirm the installation environment (temperature, humidity, cleanroom classification) meets equipment operating requirements
How FAT and SAT results affect IQ and OQ execution
A thorough FAT reduces on-site installation deviations during SAT, and a thorough SAT generates baseline evidence that directly supports IQ and OQ protocol execution. This downstream impact is one of the most important — and most overlooked — reasons to invest in rigorous acceptance testing.
When FAT identifies and resolves equipment deficiencies before shipment, the equipment arrives on site in a confirmed state. This reduces the number of open items that carry into SAT and IQ. When SAT confirms that site utilities, environmental conditions, and integration points function as specified in the URS, the IQ team can reference SAT evidence rather than re-testing the same parameters.
Incomplete FAT or SAT documentation is a leading cause of IQ/OQ delays in pharmaceutical and biotech capital projects. Validation teams that discover missing calibration certificates, unsigned punch lists, or unresolved deviations during IQ must pause qualification to remediate — adding weeks to the project timeline.
Kneat: FAT and SAT
A rapidly expanding global biotechnology company with over 45,000 employees deployed Kneat Gx to digitize its commissioning and qualification processes. After deployment, the company reduced SAT execution time by 53% — from 30 hours to 14 hours — and reduced URS approval cycle time by 88%, from 60 days to just seven days. These gains directly accelerated the company’s IQ and OQ timelines across multiple manufacturing sites.
Kneat Gx enables validation teams to execute FAT and SAT protocols digitally — capturing test evidence, managing deviations, and generating audit-ready documentation within a single platform. This eliminates the paper-based bottlenecks that slow equipment qualification and supports the traceability requirements of ISPE, GAMP 5, and EU GMP Annex 15.
Why FAT and SAT reduce qualification risk
A well-executed FAT and SAT compresses the overall equipment qualification timeline and reduces the risk of deviations during process validation. This is not a theoretical benefit — it reflects how qualification risk accumulates when acceptance testing is rushed or poorly documented.
Teams spend more time remediating equipment deficiencies they discover during IQ or OQ than deficiencies they catch at FAT. Remediation during IQ requires re-testing, additional documentation, and potential protocol amendments. Remediation during OQ may require vendor involvement, spare parts, and extended site downtime.
The earlier in the lifecycle a deficiency is identified, the lower the cost and schedule impact. FAT is the earliest practical point at which the complete system can be tested against the client’s requirements. SAT is the earliest point at which site-specific conditions can be verified. Together, they create two structured opportunities to identify and resolve issues before formal qualification begins.
Frequently asked questions
What does FAT stand for in manufacturing? FAT stands for Factory Acceptance Test. In pharmaceutical, biotech, and medical device manufacturing, a FAT is a structured test performed at the vendor’s facility before equipment ships to the client. The vendor tests the system against the client’s approved specifications to confirm the equipment is ready for shipment and on-site installation.
What does SAT stand for in manufacturing? SAT stands for Site Acceptance Test. A SAT is performed at the client’s manufacturing site after equipment installation. The client tests the system to confirm it installs correctly and integrates with site utilities, other systems, and peripherals in its intended operating environment.
Is a FAT required for all equipment in a GxP environment? Not all equipment requires a formal FAT, but any equipment procured from a third-party vendor for use in a GxP-regulated manufacturing process should have FAT and SAT incorporated into the system lifecycle. The ISPE Commissioning and Qualification Baseline® Guide and EU GMP Annex 15 both support a risk-based approach: the extent of FAT and SAT activities should reflect the complexity and criticality of the equipment.
Can a FAT be waived? A FAT can be waived when the equipment is simple, commercially available, and low-risk — or when the vendor’s quality system provides sufficient assurance of conformance. However, waiving a FAT for complex or custom-built equipment increases the risk of discovering deficiencies after shipment, when remediation is significantly more costly. Teams should document and justify any decision to waive a FAT in the project’s risk assessment.
What happens if a SAT fails? If a SAT fails — meaning the equipment does not meet the acceptance criteria in the approved SAT protocol — the team must raise a deviation, investigate the root cause, and implement a corrective action before proceeding to IQ. A SAT failure does not automatically invalidate the FAT, but it may require the vendor’s involvement if the root cause relates to equipment design or manufacturing. All SAT failures and their resolutions must be documented in the SAT deviation log.
How does FAT differ from commissioning? FAT and commissioning overlap but serve different purposes. Commissioning is the broader process of verifying that equipment and systems are installed and functioning correctly before formal qualification begins. FAT is a specific, documented test event that occurs at the vendor’s facility as part of the commissioning process. Under the ISPE Baseline® Guide, FAT is described as “partial commissioning” performed at the fabricator’s site.
How does Kneat Gx support FAT and SAT execution? Kneat Gx enables validation teams to author, approve, and execute FAT and SAT protocols digitally within a single 21 CFR Part 11 and EU Annex 11 compliant platform. Teams capture test evidence directly in the system, manage deviations in real time, and generate audit-ready documentation without paper. Kneat Gx also provides a real-time requirements traceability matrix (RTM) that links each FAT and SAT test case back to the URS, supporting the traceability requirements of ISPE and EU GMP Annex 15.
