To the casual observer, an Office Based Surgery Center (OSB) might look very similar to an Ambulatory Surgery Center (ASC). A fairly obvious difference would be that an ASC will be markedly larger than an OSB, even if they share the same specialty. Unless you are "in the business", the reason shy is not so obvious.
ASCs are licensed to bill Medicaid for services. OSBs are not. Once Government funding is involved a higher physical plant standard is required, triggering the need for significantly more space.
OSBs are governed by Local Building Codes alone (with a voluntary adherence to "Best Practices"). ASCs must not only comply with Local Codes, they must also meet National Building Standards. The FGI Guidelines for (FGI) regulate an ASCs program; what spaces are required, their minimum sizes and clearances and how they must be fitted out (sinks, cabinetry, fixtures, etc.). FGI also cross references other National Codes which regulate infrastructure and Life Safety. Such as the National Fire Protection Association (NFPA) family of codes. Both FGI and NFPA demand much higher levels of Life Safety, environmental infrastructure and infection control.
From a spatial perspective, ASCs must have; larger exam rooms, dedicated space for janitorial/housekeeping supplies, specified areas for the storage and disposition of medical waste, separate and defined storage areas for equipment, sterile supplies, general/clerical supplies, anesthesia storage (cylinders), sterilization facilities, and a room/area for the receiving and breakdown of deliveries.
Operating Rooms (ORs) in ASCs must be significantly larger than those in OSBs and can range from 250 to 400 Net Square Feet (NSF) depending on the specialty. ORs for orthopedic procedures requiring specialized equipment need to be even larger (600 NSF). The "Net Square Footage" requirement means that an OR of 400 S.F. might need to be 450 Gross Square Feet (GSF) to account for built in case work and equipment clearances. Additionally, ORs must have a minimum clear dimension of 15 feet in any direction.
