ASHRAE 43 Provides Clarity on Healthcare Ventilation Management

Key Highlights
- ASHRAE Guideline 43 provides clear operational guidance. The new guideline fills a long-standing compliance gap by offering a framework for day-to-day ventilation operations, which was not the original purpose of design standards like ASHRAE 170.
- A written ventilation management plan is best practice and is now a key expectation. This plan should guide preventive maintenance, monitoring, and documentation, ensuring a proactive and consistent response to unexpected ventilation excursions.
- The new guideline helps reduce compliance risk. By adopting ASHRAE 43 and having a documented plan, hospitals can simplify compliance and may be less likely to receive citations for minor, non-critical ventilation issues.

7 Minute Read
Any hospital facilities manager who has wondered how to respond to an unexpected ventilation excursion in their healthcare facility, or if their response meets the expectations of their infection control group and regulators now has clear direction. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) has released Guideline 43, Operations Guideline for Ventilation of Health Care Facilities, providing much-needed clarity.
For decades, healthcare facility managers (FMs) have relied on design guidance set by ASHRAE 170 or the FGI Guidelines to inform the operation of healthcare ventilation systems. Yet ASHRAE 170 was never meant to be used as an operational guideline. It provides no insight as to how to manage short excursions from temperature, humidity, or relative pressure, nor is guidance set for how often to monitor for such excursions—among many other gaps left for FMs to fill.
Accreditation organizations, including Joint Commission (JC), have likewise relied on these design standards to guide operational performance. Surveyors have seen firsthand the challenge of compliance with ventilation design standards, as this is consistently among the top most challenging requirements for healthcare facilities to meet. Some of this hardship comes from the lack of clarity in healthcare standards around ongoing ventilation management.
The Advantages of Adopting ASHRAE 43
ASHRAE 43 provides clear guidance on how to operate, maintain, test, and document elements of ventilation systems, as well as management of excursions in healthcare facilities. It also sets an expectation that healthcare FMs create a written ventilation management plan that guides preventive maintenance, establishes monitoring frequency, and identifies documentation expectations.
This provides significant advantages for healthcare FMs and all building occupants, including:
- Clarity on how to proactively address ventilation excursions. While existing guidelines may set clear design parameters for temperature, humidity, pressure, and other conditions, they provide limited framework for the allowance of planned excursions for patient comfort, medical conditions, or surgeon request. FMs have lacked guidance on what to do when systems unexpectedly perform outside the acceptable range, especially for short-duration excursions. Having a ventilation management plan in place prevents facilities teams from scrambling for a response after an unexpected variation in design conditions. Instead, teams can immediately take action, based on predetermined criteria with multidisciplinary input, to reduce risk as needed.
- Simplicity in ensuring facility compliance. Today, hospitals have the option of complying with the design standard that was relevant at the time they were built. As facilities grow, a different design standard edition may govern each addition, and potentially conflicting advice. Under ASHRAE 43, hospitals are expected to establish, using clear documentation, the standard(s) that govern each portion of their facility. Documenting this decision-making in a written plan will simplify operations and help surveyors appropriately assess compliance.
- Reduced risk of findings. As noted, accreditation organizations have likewise relied on design standards to guide expectations around ventilation system operations and excursions. And while many ventilation issues historically cited by Joint Commission under EC.02.05.01, EP 15 and EP 16 (and soon to be cited under PE.04.01.01 EP 3 when JC’s new standards go into effect in January 2026), are valid concerns, not all citations make sense in the context of day-to-day operation. For example, if a design standard sets a requirement for a room’s relative humidity to remain between 30 to 60%, does rising to 61% for an hour warrant a citation? If the facilities team responded to this excursion with appropriate action but did not document their specific response, should that prompt a warning? These are questions that both FMs and surveyors have had to address. Now, organizations have an opportunity to document their pre-determined decision-making for each individual event, which is potentially less burdensome and more standardized.
- Guidance on performing baseline inspection, space testing, and maintenance activities. Although healthcare FMs will typically already have an established preventative maintenance program in place, ASHRAE 43 provides guidelines related to inspection, testing of various user spaces, and maintenance schedules for various systems. This enables FMs to incorporate these guidelines into their current established programs based on their applicability, infrastructure capabilities, and the risk incurred in the spaces in which they operate.
The ultimate goal is that FMs will no longer be penalized for small and non-safety/infection control related excursions of “design standards” —if they have implemented ASHRAE 43 with an effective written ventilation management plan that has documentation, risk assessment, and corrective action defined within the program. That said, it will take some time for accreditation authorities to consider and potentially adopt these guidelines.
While ASHRAE 43 is currently a guideline and therefore not “required”, healthcare facilities have one more essential reason to consider implementing the guideline now: a facility’s risk of a citation may increase in the event of problems with ventilation being managed outside of the best practices outlined within this new guideline. In time, accrediting agencies may also adopt this guideline as a standard. Preparing a program today gives FMs control over the timeline for meeting ASHRAE 43 requirements, as well as protection against the use of ASHRAE 170’s design requirements inappropriately in regulatory/accreditation citations.
First steps for a ventilation management program
The good news is that while the process of creating a ventilation management program may at a glance seem overwhelming, most healthcare FMs have a similar experience upon which to draw. Within the last several years, virtually every healthcare facility has had to develop a water management program. In fact, developing a ventilation management program is likely to follow a similar pattern.
In creating a ventilation management program, healthcare FMs can expect to perform the following steps:
- Identify internal hospital stakeholders and form a committee. ASHRAE 43 sets an expectation that the FM holds responsibility for leading the ventilation management program. However, this program is best served by input from a diverse group of stakeholders. This should include infection control professionals, as well as representatives from critical spaces such as the OR.
- Assess your spaces and systems. It will be necessary to conduct an inventory of your rooms by function, differential pressure requirement, level of risk, and frequency of pressure testing or other relevant monitoring. In addition, it will be important, especially for facilities that have had construction over the years, to document which version(s) of the ASHRAE 170 guidelines are applicable to your facilities building(s). To make this process manageable, consider beginning with critical spaces before moving to noncritical areas.
- Develop a plan. FMs will need to determine a schedule for measuring pressurization, humidity, air exchange rate, and other factors in different areas of risk. They will also need to establish the steps to take in the event measurements fall outside acceptable levels, based on both the length and severity of the excursion, as well as the requirements for if and when a planned excursion may be requested (for example in response to addressing issues related to patient comfort, medical conditions, or a surgeon’s request).
- Establish policies. In addition to deciding how to document monitoring and ventilation issues, it will be important to educate staff on expectations for identifying and documenting responses to unexpected excursions or other incidents, as well as requesting a planned excursion.
FMs have time to bring ventilation in their healthcare facilities in line with ASHRAE 43. However, working with a partner who understands both ventilation system and accreditation authority expectations to develop an effective ventilation management program can simplify this process. It can also ensure your healthcare facilities are better prepared to respond to issues that could potentially threaten patient health.
If you need expert help in developing an effective ventilation management plan consistent with ASHRAE 43 guidelines for your healthcare facilities, contact EH&E today.
Subscribe
to our blog
"*" indicates required fields