Seismic Isolator Specifications and Testing: What to Require in Your RFQ
In how to choose a seismic isolator manufacturer we covered finding the right supplier. This article is about the next step: what goes into the RFQ and the supply contract. The document that protects an owner in an isolator purchase is not the catalog. A catalog is the manufacturer's claim; a specification is your requirement, and a test report is the proof that connects the two.
Three families of tests
Isolator testing answers three different questions, and none of the three can stand in for another:
- Type testing: does this product family behave the way the manufacturer claims? It qualifies the design itself, and accelerated aging tests belong to this family.
- Prototype testing: do units built to this project's parameters behave the way the design assumes? It runs on project-specific specimens.
- Production testing: does every unit shipping to the building meet the acceptance criteria? This is the quality control of the actual delivery.
Your contract needs all three defined separately. The one most often left vague is production testing, and it is the only one that verifies the bearings that actually go under your building.
The standards map
| Standard | What it covers |
|---|---|
| ASCE 7-22 Chapter 17 | The governing framework for seismically isolated buildings in the US. It sets prototype testing requirements and requires production testing of manufactured units. |
| EN 15129 | The European standard for anti-seismic devices, the usual basis for CE marking and testing requirements on European and Turkish projects. |
| ISO 22762 | Covers elastomeric bearings only. You cannot specify friction pendulum bearings against it. |
| AASHTO Guide Specifications for Seismic Isolation Design | The US reference for isolated bridges. For buildings, ASCE 7-22 Chapter 17 governs instead. |
There are two common mix-ups here. First, ISO 22762 does not cover sliding systems, so a friction pendulum purchase needs its testing basis in EN 15129 or the project specification. Second, the AASHTO guide specifications are a bridge document; citing them on a building project signals a specification written by copy-paste. For the design side of the US framework, see our article on seismic isolation design under ASCE 7-22.
Eight things to require in the RFQ
- The design parameter set: vertical load, target period, design displacement, damping. Every bidder prices the same set, otherwise the bids cannot be compared.
- A test matrix: which test, to which standard, on how many specimens. Type, prototype, and production testing each get their own lines.
- Laboratory and witnessing: testing in an accredited laboratory, with the owner's representative holding the right to witness. If the manufacturer's own lab is used, require its accreditation certificate.
- Acceptance criteria and tolerances: the allowed deviation in stiffness and damping from design values. "Complies with the standard" is not a criterion on its own.
- Proof of design life: not a promise in years but an accelerated aging test report. Standards do not assign isolators a life in years; they require proof that the unit works for the design life of the structure. More on this in isolator lifespan and maintenance.
- Traceability: a serial number, production record, and test report chain for every unit, so each delivered bearing maps to its documentation.
- Delivery and storage requirements: transport, site storage, and pre-installation inspection procedures.
- A commissioning record: a first inspection after installation, filed in the building's records. Every future periodic inspection is compared against this baseline.
Mistakes we keep seeing
- Treating a catalog line like "60-year service life" as a specification. Without a test report behind it, a life claim has no contract value.
- Accepting the manufacturer's standard test package as the test matrix. The package may not cover your project's parameters.
- Leaving out the witnessing right. Disputing a test result afterward costs far more than attending the test.
- Stopping at the prototype report. Prototype specimens are not the bearings that ship to your site; production testing is what covers those.
Conclusion
A good isolator purchase comes down to two sentences. You supply the parameters, and the manufacturer delivers behavior proven by test. The specification is what holds that bargain together, and it is cheap to write before the contract is signed and expensive to fix after.
If you want your RFQ package reviewed with this lens, book a 30- or 60-minute online consultation and we will work through the test matrix and acceptance criteria on your project.
Frequently Asked Questions
What is the difference between prototype and production testing?
Prototype testing runs on project-specific specimens to confirm the design behaves as assumed. Production testing checks the actual units delivered to the site against the acceptance criteria. A prototype report says nothing about the bearings that ship; only production testing covers those.
Can the manufacturer test in its own laboratory?
Yes, provided the laboratory is accredited and the contract gives the owner's representative the right to witness the tests. Without accreditation and witnessing, the report is only the manufacturer's own statement.
Does ISO 22762 cover friction pendulum bearings?
No. ISO 22762 covers elastomeric bearings only. Testing requirements for friction pendulum systems are specified through EN 15129 or the project specification.
What are the AASHTO Guide Specifications for Seismic Isolation Design?
An AASHTO document for seismically isolated bridges in the US. It is not the right reference for a building project; buildings fall under ASCE 7-22 Chapter 17.
How many years of warranty should I ask for?
Standards do not assign isolators a service life in years. They require proof, through accelerated aging tests, that the unit works for the design life of the structure. Ask for the aging test report and a periodic inspection program instead of a number of years.
Read this article in Turkish: İzolatör Şartnamesi ve Kabul Testleri: Üreticiden Ne İstemelisiniz?