FAT VS ROUTINE TEST
Two different levels of factory verification for AGL equipment such as CCRs and control panels. A Factory Routine Test asks whether the individual manufactured unit was built correctly, while a Factory Acceptance Test (FAT) asks whether that unit meets the specific project's contract, drawings and functional requirements before it ships.
At a Glance
| Feature | FAT | Factory Routine Test |
|---|---|---|
| Full form | Factory Acceptance Test | Routine Test |
| Purpose | Project acceptance | Production quality verification |
| Performed | Factory | Factory |
| Scope | Project-specific | Standard / manufacturer-defined |
| Applied to | Selected equipment/system as specified | Normally every manufactured unit |
| Witness | Client/consultant may witness | Usually manufacturer/QA |
| Timing | Before shipment | During/after manufacturing |
| Test criteria | Approved FAT procedure/specification | Applicable product standard + manufacturer's procedure |
| Documentation | FAT report/protocol | Routine test certificate/report |
| Main focus | Compliance and functionality | Manufacturing quality and consistency |
Two Different Questions
FAT verifies that the equipment meets the project-specific requirements before shipment, usually with client/consultant witnessing. A Factory Routine Test verifies that each manufactured unit has passed the manufacturer's standard production tests.
In one line, each test answers a different question:
Production-Stage Verification
A routine test is essentially a production test. Its objective is to confirm that the individual manufactured unit is free from defects that can be detected through the specified routine tests.
MANUFACTURING
↓
ASSEMBLY
↓
ROUTINE TEST
↓
PASS?
↙ ↘
NO YES
↓ ↓
REWORK RELEASE
For example, an AGL CCR may undergo routine checks such as:
- Visual inspection
- Wiring verification
- Insulation-related tests
- Dielectric/withstand test where applicable
- Functional checks
- Protection checks
- Output verification
- Metering verification
The exact routine tests depend on the equipment type and applicable product standard.
Project-Stage Verification
FAT is more closely linked to the project contract than to the product standard alone.
MANUFACTURED EQUIPMENT
↓
ROUTINE TEST
↓
FAT SETUP
↓
PROJECT-SPECIFIC TESTS
↓
CLIENT / CONSULTANT
WITNESS
↓
FAT PASS
↓
SHIPMENT
The FAT may verify:
- Approved drawings
- Nameplate details
- Project-specific ratings
- Functional, control and protection operation
- Alarm indications
- Remote-control and monitoring interfaces
- Communication and interlocks
- Performance requirements
Standard vs Project Requirement
This is the single most useful distinction between the two tests: what each one is tested against.
PRODUCT
STANDARD
+
MANUFACTURER
PROCEDURE
↓
ROUTINE TEST
PROJECT
SPECIFICATION
+
APPROVED DRAWINGS
+
FAT PROCEDURE
+
APPLICABLE STANDARDS
↓
FAT
So FAT can include requirements that are not part of the normal routine production test.
A 6.6 A CCR at the Factory
Suppose an airport purchases a 6.6 A CCR. The two tests cover different ground.
6.6 A CCR
│
├── Visual inspection
├── Wiring check
├── Electrical safety tests
├── Functional test
├── Output verification
└── Protection verification
6.6 A CCR
│
├── Nameplate verification
├── Approved drawing verification
├── Current step verification
├── Output regulation
├── Alarm simulation
├── Remote control
├── Monitoring
├── Communication
├── Interlocking
└── Project-specific functions
The routine test establishes that the manufactured CCR passed the required production tests. The exact FAT scope, on top of that, comes from the approved project FAT procedure.
Attendance at Each Test
MANUFACTURER
│
▼
QA / QC
│
▼
ROUTINE TEST
MANUFACTURER
+
CLIENT
+
CONSULTANT / INSPECTOR
│
▼
FAT
Client attendance at a routine test is generally not necessary unless the contract specifically requires it. At a FAT, the customer may witness the agreed tests before accepting the equipment for shipment.
Is Every Unit Tested?
Generally, each manufactured unit is subjected to the specified routine tests, while FAT sampling or quantity is project-specific.
10 CCRs manufactured Routine Test: 10 / 10 units → tested FAT: 1 or selected units → witnessed, if specified by the project
Do not assume a particular FAT sampling percentage unless the contract or approved inspection and test plan specifies it.
What Gets Recorded
CCR Serial No.: XXXXX Routine Test: ✓ Electrical test ✓ Functional test ✓ Output test ✓ Protection test RESULT: PASS
PROJECT: AIRPORT AGL Equipment: CCR Model: XXXXX FAT ITEMS: ✓ Visual inspection ✓ Drawing verification ✓ Functional test ✓ Current steps ✓ Protection ✓ Alarm ✓ Remote control ✓ Monitoring CLIENT WITNESS: YES RESULT: ACCEPTED
A routine test certificate typically records equipment identification, serial number, test date, test values, the applicable standard/procedure, the test result and manufacturer QA approval. A FAT report is usually more detailed and project-oriented.
FAT Can Build on Routine-Test Results
A FAT does not necessarily have to repeat every production test.
ROUTINE TEST
│
▼
CERTIFICATE AVAILABLE
│
▼
FAT
│
├── REVIEW ROUTINE TEST RECORDS
│
├── PERFORM REQUIRED
│ PROJECT TESTS
│
└── WITNESS FUNCTIONAL TESTS
The FAT procedure may require review of the routine test certificates rather than repeating every test.
Think of a New Car
Factory Routine Test
The manufacturer checks: "Was this particular car built correctly?"
FAT
The customer checks: "Does this car meet the configuration and requirements I ordered?"
ROUTINE TEST
↓
MANUFACTURING QUALITY
FAT
↓
CUSTOMER / PROJECT ACCEPTANCE
Side-by-Side Parameters
| Parameter | Factory Routine Test | FAT |
|---|---|---|
| Primary objective | Manufacturing quality | Project acceptance |
| Basis | Product standard/manufacturer procedure | Project specification + approved FAT procedure |
| Frequency | Generally each unit | As specified by project |
| Client witness | Usually no | Often yes |
| Project-specific tests | Limited | Yes |
| Production defects | Primary focus | Also checked |
| System functionality | Basic/defined production checks | Detailed project functionality |
| Remote interface | May not be included | Often included where applicable |
| Documentation | Routine test certificate | FAT report/protocol |
| Shipment release | Supports release | Often linked to acceptance/release |
Three Layers of Verification
For equipment such as CCRs, AGL control panels, remote monitoring systems, control and communication panels and packaged AGL equipment, the routine test and FAT should not be treated as identical tests. A good sequence carries the equipment through three distinct stages before it ever reaches site.
MANUFACTURING
↓
ROUTINE TEST
↓
ROUTINE TEST CERTIFICATE
↓
FAT
↓
CLIENT / CONSULTANT ACCEPTANCE
↓
DISPATCH
↓
SITE INSTALLATION
↓
SAT
This gives three different levels of verification: Routine Test → FAT → SAT.
- Routine Test: Manufacturing quality
- FAT: Project/equipment acceptance
- SAT: Installed system acceptance
FAT vs Factory Routine Test
Factory Routine Test = standard production test performed to verify the quality and functional condition of the individual manufactured unit.
FAT = project-specific acceptance test performed at the factory to confirm that the equipment meets the contract, approved design and functional requirements before shipment. For an AGL project, the strongest QA/QC approach is to treat Routine Test, FAT and SAT as three separate acceptance layers rather than using the FAT as a substitute for routine testing or SAT.
Routine Test and FAT are complementary, not interchangeable — a FAT that only re-runs routine checks has not actually confirmed project acceptance, and a routine test can never substitute for witnessed, project-specific verification.
Engineering & Expert Notes
Define FAT Criteria Before the Visit
PreparationAgree the test list and acceptance values in advance so the visit can be efficient.
Witness Critical Tests
WitnessingAttend or delegate a competent witness for key tests, and sign the records.
Obtain the Routine Test Report With Each Unit
RecordsLink it to the serial number and keep it for later reference.
Record and Close Out Any Deviation
Non-ConformanceDocument findings, rectification and retest before release.
Frequently Asked Questions
A Factory Routine Test verifies that an individual manufactured unit was built and tested correctly against the product standard and manufacturer's procedure. FAT verifies that the unit meets project-specific requirements and acceptance criteria, typically witnessed by the client or consultant.
Generally, yes — each manufactured unit is subjected to the specified routine tests as part of normal production. FAT quantity or sampling, by contrast, is project-specific and should not be assumed unless stated in the contract or approved inspection and test plan.
Not necessarily. A FAT procedure may require review of the routine test certificates rather than repeating every production test, then add project-specific tests and witnessed functional checks on top.
Routine tests are usually witnessed by the manufacturer's own QA/QC function, with client attendance not normally required unless the contract specifies it. FAT is typically witnessed by the manufacturer together with the client and/or an appointed consultant or inspector.
No. Routine testing and FAT serve different purposes. The recommended approach is to treat Routine Test, FAT and SAT as three separate acceptance layers rather than substituting one for another.
FAT is performed at the factory before shipment to confirm project acceptance of the equipment itself. SAT (Site Acceptance Test) is performed after installation to confirm that the installed system works correctly at site. They are sequential, not interchangeable, stages of verification.
Governing Documents
For an actual project, always verify the current edition of the applicable documents and the project's own approved inspection and test plan.
Equipment Product Standards
The applicable product standard for the equipment type (e.g. low-voltage switchgear/CCR panel standards) defines the routine tests every manufactured unit must pass.
Project FAT Procedure & ITP
The approved project specification, contract, approved drawings and Inspection and Test Plan (ITP) define the FAT scope, sampling and witnessing requirements.
ICAO Annex 14 / FAA AC 150/5345 Series
Aerodrome design and equipment advisory documents that inform the overall AGL equipment acceptance and testing framework referenced by many project specifications.
Final Engineering Note
Do not assume a generic FAT scope or sampling rate. The final test procedure should always be developed from the current governing standard, the approved project specification and the client/consultant-agreed ITP.
A Factory Routine Test is not a substitute for FAT, and a FAT is not simply a repeat of routine testing — each verifies a different question at a different stage of acceptance.
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