ASHRAE recently announced the publication of ANSI/ASHRAE/ASHE Standard 170-2013, Ventilation of Health Care Facilities.

Under constant maintenance since its initial publication in 2008, the standard features updates, changes, and clarifications concerning humidity, ducted returns, recirculating room units, duct lining, and more.

Standard 170-2013 includes provisions for the application of energy recovery. As stipulated, energy-recovery systems cannot allow cross-contamination of exhaust air back to supply-air streams. Run-around coils are an example of a system that is permitted.

Standard 170-2013 allows relative humidities as low as 20 percent for some rooms. This may result in smaller-capacity humidification equipment, lower operating costs, and reduced maintenance costs. The standard permits some use of plenum returns in outpatient facilities, which, in turn, may result in lower construction and operating costs.

Additionally, the standard addresses the application of displacement ventilation in patient rooms.

The cost of ANSI/ASHRAE/ASHE Standard 170-2013 is $48 for ASHRAE members and $58 for non-members. Copies can be ordered by phone at 1-800-527-4723 (United States and Canada) or 404-636-8400, by fax at 678-539-2129, or online at