HCAI Building Classifications: OSHPD 1, 1R, 2, 3, 4 and 5
Every California healthcare building regulated by HCAI (formerly OSHPD) is assigned a building classification. That classification decides how much seismic performance the structure and its nonstructural systems must deliver — and whether the equipment you are installing needs OSP preapproval or a project-specific certification.
Classification comparison
| Type | What it covers | Seismic expectation |
|---|---|---|
| OSHPD 1 | General acute care hospital buildings | Must remain operational after a design earthquake — SPC and NPC ratings assigned |
| OSHPD 1R | Acute care buildings undergoing retrofit or reclassification | Interim compliance path toward SPC-4/SPC-5 and NPC targets |
| OSHPD 2 | Skilled nursing and intermediate care facilities | Life-safety performance; anchorage per CBC/ASCE 7-22, no SPC rating |
| OSHPD 3 | Clinics and outpatient facilities | Code-compliant anchorage; HCAI review only where licensing requires it |
| OSHPD 4 | Correctional treatment centers | Acute-care-level structural and nonstructural requirements |
| OSHPD 5 | Licensed acute psychiatric hospitals | Acute-care-level requirements with program-specific exceptions |
OSHPD 1 vs OSHPD 2 — the distinction that matters most
OSHPD 1 buildings are general acute care hospitals. Under the Alfred E. Alquist Hospital Facilities Seismic Safety Act they must remain operational after a design earthquake, not merely standing. That drives an importance factor of Ip = 1.5 on essentially all designated nonstructural components, certified anchorage for mechanical and electrical equipment, and full HCAI plan review.
OSHPD 2 buildings — skilled nursing and intermediate care — are held to a life-safety standard. Anchorage still has to satisfy the California Building Code and ASCE 7-22 Chapter 13, but there is no SPC rating and the certification burden on equipment is lighter.
SPC ratings — structural performance
SPC (Structural Performance Category) describes how the building frame is expected to behave in a design earthquake:
- SPC-1 — significant risk of collapse; must be retrofitted or removed from acute care service.
- SPC-2 — does not meet current standards but is not judged a collapse risk.
- SPC-3 — expected to remain standing; may not be usable afterward.
- SPC-4 — expected to remain standing and repairable, with limited damage.
- SPC-5 — expected to remain fully functional; the long-term target for acute care.
NPC ratings — nonstructural performance
NPC (Nonstructural Performance Category) rates the bracing and anchorage of everything that is not the frame — equipment, piping, ductwork, ceilings, communications, and emergency power. This is where most of our work lives:
- NPC-1 — minimal bracing of nonstructural systems.
- NPC-2 — bracing of communications, emergency power, and select systems.
- NPC-3 — adds bracing of critical piping, medical gas, and fire protection.
- NPC-4 — adds on-site water and holding, plus broader equipment anchorage.
- NPC-5 — full nonstructural compliance so services continue after an earthquake.
Raising an NPC rating almost always means producing stamped seismic anchorage calculations for existing and new equipment, plus hospital equipment anchorage details for the contractor.
How classification affects your submittal
- OSHPD 1 / 1R / 4 / 5 — designated equipment needs an HCAI OSP, an OPM listing, or project-specific certification under CBC / ASCE 7-22 §13.2.2, usually backed by AC156 shake-table testing. Check the OSP database and PCS database before designing from scratch.
- OSHPD 2 / 3 — stamped anchorage calculations to the California Building Code, typically without HCAI preapproval listings.
Related resources
- What does OSHPD mean? OSHPD vs HCAI
- OSHPD seismic requirements checklist
- HCAI seismic certification services
- Nonstructural component certification
- Free OSP database — search listings
Not sure which classification your project falls under?
Send us the facility type and equipment list — we will confirm the certification path and quote stamped calculations within 24 hours.
Request stamped calculationsFrequently asked questions
- What is the difference between OSHPD 1 and OSHPD 2?
- OSHPD 1 covers general acute care hospital buildings that must remain operational after a design earthquake, so they carry the strictest structural (SPC) and nonstructural (NPC) performance requirements. OSHPD 2 covers skilled nursing and intermediate care facilities, which must protect life safety but are not required to stay fully functional after an earthquake.
- What are the HCAI building classifications?
- HCAI (formerly OSHPD) uses six classifications: OSHPD 1 (acute care hospitals), OSHPD 1R (acute care buildings under retrofit or reclassification), OSHPD 2 (skilled nursing and intermediate care), OSHPD 3 (clinics and outpatient facilities), OSHPD 4 (correctional treatment centers), and OSHPD 5 (licensed acute psychiatric hospitals).
- What do SPC and NPC ratings mean?
- SPC (Structural Performance Category, SPC-1 through SPC-5) rates how a hospital building's structure is expected to perform in a design earthquake. NPC (Nonstructural Performance Category, NPC-1 through NPC-5) rates the anchorage and bracing of nonstructural systems — equipment, piping, ducts, ceilings, and utilities. Higher numbers mean better expected post-earthquake performance.
- Which OSHPD classifications require seismic certification of equipment?
- OSHPD 1, 1R, 4 and 5 buildings require certified anchorage and, for designated systems, HCAI OSP/OPM preapproval or project-specific certification under CBC/ASCE 7-22 §13.2.2. OSHPD 2 and 3 buildings still require code-compliant anchorage calculations, but the certification burden is lighter.
- Does OSHPD 3 require HCAI plan review?
- OSHPD 3 clinics are generally reviewed by HCAI only when licensing requires it; many outpatient clinics are permitted by the local building department instead. The seismic anchorage requirements of the California Building Code still apply either way.