OSHPD Generator Seismic Certification
Emergency and standby gensets serving California hospitals are Iₚ = 1.5 by default — they must run after the Design Earthquake. That means AC156 shake-table qualification, an OSP pre-approval or project-specific certification, and a properly engineered isolator + snubber base.
Four certification paths for generators
Because every hospital genset is Iₚ = 1.5, analysis-only certification is not allowed. The genset must be qualified by AC156 shake-table testing — either through a reusable OSP listing, or as a one-time project package paired with a tested isolator family.
OSP pre-approval
For genset OEMs and packagers selling the same model into California hospitals. One AC156 test program, reusable across every project.
Learn moreAC156 shake table testing
Mandatory for Ip = 1.5 generators. Includes engine, alternator, controls, and the isolator/snubber base — all tested as one assembly.
Learn moreVibration isolation & snubbers
Engineered isolator + snubber selection sized for the genset's operating weight, CG height, and SDS at the project site.
Learn moreProject anchorage letter
PE/SE-stamped calc package for a specific genset on a specific pad when OSP isn't justified.
Learn moreWhy isolator selection matters for generator OSP
The OSP applies to the tested assembly — engine, alternator, controls, and the specific isolator/snubber base used during AC156. Swap the isolator on the project and the OSP no longer covers the install.
If the spec'd isolator isn't covered by the genset OSP envelope or a separate OPM, you're either re-testing or producing a project-specific certification package. We help packagers map the OSP envelope to commonly spec'd isolator families to avoid this trap.
What we need to scope a generator cert
- Genset cut-sheet, dry/wet operating weight, and CG height
- Mounting: rigid skid, spring isolators, or housed restrained isolators
- Existing OSP/OPM number (if certifying a substitution)
- SDS at the project site (from geotech / structural engineer)
- Hospital project number and HCAI office (Northern / Southern CA)
- Sub-base fuel tank — included in the assembly or anchored separately?
Quote a generator cert in 24 hours
Send us the genset cut-sheet, weight, isolator model, and Ip designation. You'll have a scoped, itemized PE/SE-stamped proposal — typically within one business day.
PE/SE stamped • Hundreds of California hospital projects since 2008