Friday, July 30, 2021
AHU two stage filtration system with panel and box filters

As mentioned in the previous blog post, ANSI/ASHRAE/ASHE Standard 170-2021 recommends a wide range of particle efficiency based upon the “Function of Space” within a healthcare facility. To break it down further, we developed the table below.

Type of Space

Required Particle Efficiency*

Typical Filters

Least Critical


Pleated Filters

Moderately Critical

MERV 14 or MERV 16

Box Filters, Possibly Bag Filters

Most Critical

HEPA Filtration

HEPA Filters

 *As noted in the blog post Revised Standard Provides Clean Air Guidance for Healthcare Facilities, the updated standard requires air filters that rely on a mechanical means of filtration to avoid possible degradation of particle efficiency over time.

For an overview of air filtration solutions work to ensure clean air throughout your facilities, visit our Healthcare Market Insights page.

To better understand the implications of this updated standard for air filtration in your facility, download this infographic.

For more information on the revised standard, check out this handy blog post shared by the professional associations.