Follow us on Twitter Friend us on Facebook Look for us on Google Plus Share with your Friends Print this Page
Friday 8:19 CST, December 19, 2014


Download This Issue (PDF)


August 14, 2013

CMS adopts ASHRAE-defined range for relative humidity in anesthetizing locations


Achieving the right balance of humidity in anesthetizing locations, such as the operating room, can be challenging. Too much moisture in the air can lead to mold growth, while too little presents the opportunity for static electricity, increasing the possibility of fire if a spark ignites a fuel source near combustible material. Over the years, the requirements for relative humidity levels in anesthetizing locations have evolved as underlying risk factors have changed. The National Fire Protection Association (NFPA), the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), and The Joint Commission have worked with the Centers for Medicare & Medicaid Services (CMS) to come up with a cost-effective relative humidity range that meets patient safety requirements.

On April 19, 2013, CMS adopted the ASHRAE-defined range for relative humidity, issuing the “Waiver of Life Safety Code Anesthetizing Location Requirements” (S&C 13-25-LSC & ASC). The waiver adjusts the lower range of relative humidity to 20 percent, which aligns with the Facilities Guidelines Institute’s (FGI) 2010 edition of Guidelines for Design & Construction of Health Care Facilities. CMS requires that an organization declare at the beginning of any CMS-conducted survey that it has elected to use this waiver. Organizations must document their decision to use the waiver; in addition, they must demonstrate compliance with the ASHRAE standard by documenting the range in which they plan to keep humidity levels. Possible ways to communicate this information include:

  • Annotating the Statement of Conditions™ in the Basic Building Information (BBI) in the “Additional Comments” text box
  • Delineating the humidity range in organization policy

Either of these methods is acceptable, but the preferred approach is to involve the safety or environment of care committees in the decision about appropriate humidity levels. The decision would then be documented in committee minutes. Once a range has been identified, a health care organization must monitor (and document) relative humidity levels in anesthetizing locations and respond when levels are out of range. See the August 2013 issue of Joint Commission Perspectives for more information, including a summary of the “Waiver of Life Safety Code Anesthetizing Location Requirements.” (Contact: George Mills,




To post a comment, Log In or Sign Up
No comments have been posted, be the first one to comment.
« Back

This website is certified by Health On the Net Foundation. Click to verify. This site complies with the HONcode standard for trustworthy health information:
verify here.