Air Pressure Relationships

Q: We have operating rooms with two doors, one that is adjoining to the sterile corridor and one to the common corridor in the Surgery department. We monitor the common corridor continuously through our building automation system (BAS). We do not monitor the sterile corridor. Is there a requirement to monitor the sterile corridor continuously or daily?

A: The standards on monitoring and logging are weak on ventilation requirements and not well defined in many cases. But the expectation is your organization will be monitoring and logging certain environmental parameters regarding operating rooms, such as:

• Air-pressure relationship to surrounding areas;
• Humidity levels;
• Temperature levels

For new construction, CMS and the accreditation organizations recommend compliance with industry standards such as FGI Guidelines, AORN, CDC, and the like when other state or local regulations are silent. For existing conditions, most accreditation organizations have standards that require you to maintain ‘appropriate’ pressure relationships, air-exchange rates, filtration efficiencies, temperature and humidity, based on the edition of the design standards used at the time of design… if you know when that was, and what document was used for the design.

Many organizations don’t have that information available to them. When that is not known, most surveyors will lean on what is currently required for temperature, humidity, and air-pressure relationships. The FGI Guidelines require a positive air-pressure relationship to surrounding areas for operating rooms. That would include all areas, including the sterile OR corridor. I believe CMS and the accreditation organizations would expect you to monitor the air-pressure relationship between the operating room and all other areas, including the sterile corridor. There is no requirement to monitor this on a continuous basis, but should be conducted prior to every case.