ASHRAE+62.1-2022+(1) - Page 052
Extracted Content
(This appendix is not part of this standard. It is merely informative and does not contain requirements necessary for conformance to the standard. It has not been processed according to the ANSI require- ments for a standard and may contain material that has not been subject to public review or a consen- sus process. Unresolved objectors on informative material are not offered the right to appeal at ASHRAE or ANSI.)
INFORMATIVE APPENDIX G SIMPLIFIED VENTILATION RATE CALCULATION FOR MULTIPLE-ZONE RECIRCULATING SYSTEMS SERVING ONLY SPECIFIED OCCUPANCY CATEGORIES IN EXISTING BUILDINGS
G1. USE OF THIS APPENDIX
This appendix is intended to be used to assess ventilation rates in existing buildings for third-party building evaluation programs such as ASHRAE Building EQ (bEQ), Leadership in Energy and Environmental Design for Existing Buildings: Operations and Maintenance (LEED EBOM), Energy Star, etc. Zone minimum primary airflow is included as guidance in evaluating and adjusting minimum box settings. This informative appendix is not intended to be used as the Basis of Design or for regulatory applications.
G2. OUTDOOR AIR INTAKE
For multiple-zone recirculating systems serving only occupancy categories listed in Table G-1, the target outdoor air intake flow ( Vtarget ) is determined in accordance with Equation G-1. For all other systems, Vtarget is set equal to Vot in accordance with Section 6.2.4.4. If the minimum outdoor air intake flows measured at the system level meet or exceed Vtarget, then the system meets the criteria of this informative appendix.
Vtarget = all zones Az × Rs (G-1)
where
Az = zone floor area, the net occupiable floor area of the ventilation zone, ft [2] (m [2] )
Rs = outdoor airflow rate required per unit area as determined from Table G-1
G3. ZONE MINIMUM PRIMARY AIRFLOW
For each zone, the minimum primary airflow ( Vpz-min ) is determined in accordance with Equation G-2.
Vpz-min = Az × Rpz (G-2)
where
Rpz = minimum primary airflow rate required per unit area as determined from Table G-1. This is the minimum zone airflow required for ventilation purposes.
50 ANSI/ASHRAE Standard 62.1-2022