855773520-LEED-v5-ID-C-Reference-Guide-Launch-Edition-1 - Page 311

Extracted Content

FILTRATION

This prerequisite has additional filtration requirements beyond those in ASHRAE 62.1 . MERV 13 filtration (and ePM1 50%) is becoming standard practice, and most HVAC systems can be designed to easily accommodate this level of filtration. The filtration requirements apply to all central HVAC systems that supply outdoor air, recirculated air, or outdoor air and recirculated air to regularly occupied spaces. Projects that use base building ventilation systems will need to confirm that those systems comply.

MERV 13 filtration is not required for systems that supply air to warehouses or other areas addressed in the ASHRAE exemption for outdoor air treatment

Exemption to 6.1.4 Systems supplying air for enclosed parking garages, warehouses, storage rooms, janitor’s closets, trash rooms, recycling areas, and shipping/receiving/distribution areas are exempt.

An alternative approach that allows in-room air cleaning systems to be used offers flexibility in meeting this prerequisite requirement for situations where design constraints make the central system-level filtration requirement infeasible or impractical.

AIR CLEANING SYSTEMS

Air cleaning systems may be used in the design to meet the prerequisite requirements. Before selecting the air cleaning system, ensure the manufacturer has a safety testing report and manufacturer certification that the product is safe. Verified effectiveness values also provided by the manufacturer must be used in the design calculations as applicable.

• Safety . All air cleaning systems require safety testing according to ASHRAE Standard 241-2023, Section 7.4 and Normative Appendix A. This standard has the most up-todate language to assess safety, which includes addressing chemical emissions and some potential byproducts, ultraviolet radiation, combustion byproducts, and noise generated during operation. Testing is conducted in a specialized test chamber with specific environmental controls. [113]

• Effectiveness for particle filtration efficiency or gaseous removal efficiency . For systems that treat particles and gases, use only systems that have a verified effectiveness determined according to ASHRAE Standard 62.1-2022, Addendum N.

• Effectiveness for infectious aerosols . For systems being selected to treat infectious aerosols and meet the minimum equivalent clean airflow rates outlined in ASHRAE

113 “Control of Infectious Aerosols”, ASHRAE, (2023), accessed March 31, 2025, https://www.ashrae.org/file%20library/technical%20resources/standards%20and%20guidelines/standards%20addenda/241_2023_a _20241021.pdf.

U.S. Green Building Council LEED v5 Reference Guide for Interior Design and Construction, April 2025 Launch Edition 300