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Q-PAC‘s Q-PAC Multimotor Plenum Fan (MPF) is now covered under HCAI Special Seismic Certification Preapproval OSP-0875, giving engineers a seismically certified fan option for critical facilities and high-seismic regions. This positions the Q-PAC MPF as a code-compliant solution for new construction and retrofit air handler projects that must meet International Building Code (IBC) and California Building Code (CBC) seismic requirements.
The Q-PAC Fan is certified through HCAI’s Special Seismic Certification Preapproval program as OSP-0875, based on full-scale three-dimensional shake table testing to ICC-ES AC156 criteria for nonstructural components. The complete MPF system, including all plug fan models, the frame, and the Q-PAC control panel, was tested at the University of Nevada, Reno, and certified by Pre Compliance for IBC 2024 and CBC 2025. These results were then reviewed and accepted by an independent California structural engineer and HCAI.
Under OSP-0875, the Q-PAC Fan is certified up to SDS 2.50 g for grade-level installations and up to SDS 1.61 g for roof or elevated installations, including height effects, which covers almost all of the United States and most of California. With importance factor Ip 1.5, the fan is expected to stay anchored during a design-level earthquake and continue operating afterward, which is essential for critical facilities.
The certification targets essential facilities such as hospitals, laboratories, and other critical infrastructure. It demonstrates that the fan system can withstand earthquake shaking and maintain operation at the specified seismic demands, providing a clear, code-based path that reduces risk and back-and-forth during plan review and inspection.
For new construction, the MPF seismic preapproval is especially valuable in air handlers that already have a seismic OSP and list a fan array. When an air handler has its own OSP and uses a fan array, the Q-PAC Fan can be treated as an equivalent preapproved fan system when the mounting has similar four-sided support, with sheet metal of equal or greater thickness and similar screw spacing and pattern, effectively making it a preapproved ECM fan system under OSP-0875.
For retrofits, the Q-PAC Fan supports a three-bucket framework for seismically active markets. In seismically certified air handlers that originally listed a fan array, replacing that array with a Q-PAC Fan of similar or lower weight, and similar support is generally low risk and consistent with the code. Certified air handlers with blowers, non-certified legacy air handlers, and very high SDS sites will still require site-specific engineering and review, but can leverage OSP-0875 as strong test evidence.
One of the major advantages of this certification is that it makes the MPF one of the only retrofit options with a standalone fan OSP. The Q-PAC Fan’s modular design can be broken down, moved through doors and elevators, and assembled inside existing mechanical rooms. Unlike many seismically certified fans tied to a specific OEM cabinet or intended only for ducted or rooftop installations, the Q-PAC Fan combines a field-installable multimotor plenum fan with standalone HCAI seismic preapproval for the fan system itself, enabling retrofit applications across multiple OEM air handlers.
The Q-PAC Fan is preapproved as a standalone fan system, not just as part of a specific OEM unit. This gives engineers a defensible substitution path for like-for-like air handler replacements when the mounting arrangement is comparable. Q-PAC and its structural partner provide engineering letters and supporting documentation tying the tested configuration to the proposed installation, helping design professionals and special inspectors verify that the installed unit matches the certified configuration.
The Q-PAC Fan seismic certification also supports California’s 2030 hospital seismic deadline, which requires general acute care hospital buildings in service after January 1, 2030 to meet structural and nonstructural seismic requirements for critical systems. With HCAI Special Seismic Certification Preapproval OSP-0875, the Q-PAC Fan gives hospitals, laboratories, and other essential facilities a seismically certified fan system solution designed to stay anchored and keep operating during and after a design-level earthquake.
