What are FAT and SAT? Differences, Objectives & Advantages

Taking care of the quality of products, services, and care is essential. However, the FAT and SAT inspections are essential to be able to verify the quality, and efficiency of industrial products.

FAT and SAT are often confused since both refer to tests or product tests. The FAT is carried out at the customer’s location. That is, where the equipment is going to be used.

Both the SAT (Site Acceptance Test) and FAT (Factory Acceptance Test) tests are validation tests, they just take place in different locations. The SAT is in place of use or operation, and the FAT is in the factory within its production process.


The SAT and FAT are types of inspections, distinguished by a high level of demand and thoroughness, to ensure that accurate results are obtained.

Quality- FAT and SAT

Purpose of FAT and SAT

The FAT and SATs by definition search for the same objective, guaranteeing proper functioning within defined parameters of quality and safety. While the on-site tests (SATs) are carried out at the equipment installation location, the FAT tests are those that are carried out at the supplier’s factory location. It is before the product or equipment leaves for its destination.

Difference between FAT and SAT

What are the Factory Acceptance Tests (FATs)

FAT tests are those that are carried out to validate, in the factory, that a piece of equipment carries out its entire process correctly and efficiently.

These tests consist of carrying out a series of steps, previously stipulated and ordered. Once manufacturing has finished and before sending the product to the buyer. Along with them, it is verified that the supplied equipment works properly.

FAT tests are performed in the presence of the client or the person designated by the client. Once completed, a sealed copy is sent with all the documentation resulting from the tests so the client can approve the equipment and proceed with its shipment and installation.

What are the Site Acceptance Tests (SATs)?

The SATs are those that are carried out in the final location of the equipment. That is, once it has already been installed or placed in the client’s facilities.

These tests are also carried out in the presence of the customer and are used to show how the equipment works, how it is set up, etc. For this, it is necessary that the technical personnel that will use the installed equipment be present and can resolve all the doubts that may arise.

Objectives of FAT and SAT

The main objectives of the FAT test are the following:

  • FAT demonstrates to the customer that the equipment they want to purchase meets all the specifications that have been promised to the user. That may be in terms of production, operation, maintenance, and safety.
  • Helps to verify the quality of the entire manufacturing process, assembly, configuration, software, etc.
  • To assure the performance of the equipment according to the specifications requested by the client at the time of purchase.
  • Factory acceptance test carries out the analysis that the client requests. It will be verified that the operation is adequate, or complete, in which case a real test will be performed.

The main objectives of the SATs are as follows:

  • Helps to check the initial configuration of the device.
  • Ensure that the installed product functions correctly according to the specifications requested by the customer at the time of purchase.
  • Verify that configuration, functionality, and performance requirements are met.
  • Providing training to the customer’s technical team so that they can make good use of the equipment.
  • Helps to check and correct any type of error that installed equipment presents to offer maximum security.
  • Check the physical inputs and outputs of each control device.
  • Checking out a visual check of the system and all its components.
  • Check software and mechanical system.
  • Check that the HVAC (internal pressure and ventilation) is adequate.

What are the FAT and SATs for?

The FAT and SATs are used to implement the equipment’s warranty. Also, to properly configure it following the customer’s specifications. Check and verify that everything works properly.

In case of operating problems, they also make it possible to adjust controls and correct errors. In addition, they are used to train the technical team that will be in charge of using the equipment or machinery.

Are the FAT and SAT inspection compulsory to perform?

The SAT and FAT tests are not essential but are very helpful. They serve to increase the level of customer satisfaction with the company. As well s to make them feel more secure and confident in the proper use of the equipment purchased.

In addition, with all the sealed documentation of the tests carried out, the client can better manage the risk assessment. Management can plan further to get the most out of their new acquisition and increase the profitability of their business.

Advantages of FAT tests

FAT tests have been an essential element in the production process for some time, as they provide many benefits.

  1. Factory acceptance tests reduce manufacturing costs by optimizing all processes to reduce the number of errors. In addition, they will ensure that less equipment ends up back due to incorrect operation or breakdowns.
  • Increase the quality offered to the end user. It is by improving their level of satisfaction with the company.
  • They allow the detection of problems that were not detected during the design and production phases.
  • They facilitate the correction of errors, preventing a product or equipment from reaching the market with problems.
  • They bring benefits, both to the end customer and to the manufacturer himself.

FAT/SAT Results

After carrying out FAT and SAT, if satisfactory test results are obtained based on the acceptance criteria, this phase is concluded and acceptance protocols are signed.

If unsatisfactory results are obtained, the corresponding report is prepared and requested for corrections. Reports are generated on equipment supply, installation, and performance.


The FAT and SATs are a guarantee of the quality of the equipment that is being installed.

As said in the above paragraphs, SAT and FAT are not mandatory. But they are a very good option so that customers can improve their degree of satisfaction with the purchase. In addition, adjust all the controls of the equipment to their own needs.

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