Energy in Buildings - Energy Efficiency in the Urban Environment - page 127

and target concentrations shall be shown in the design documents. Outdoor air
CO 2 concentrations shall be determined by one of the following:
1. CO 2 concentration shall be assumed to be 400 ppm without any
direct measurement
2. CO 2 concentration shall be dynamically measured using a CO 2
sensor located near the position of the outdoor air intake
6.2.6 Filtration and Air Cleaner Requirements
6.2.6.1 Particulate Matter
1. The particulate matter filters or air cleaners shall have an Minimum
Energy Values (MERV) of not less than 8 and shall comply with and
be provided where required in Section 5.9 of ASHRAE Standard 62.1.
2. In addition to ASHRAE Standard 62.1 Section 6.2.1.1, when the build-
ing is located in an area that is designated 'non-attainment' with the
National Ambient Air Quality Standards for PM2.5 as determined
by the American Heating Institute (AHI) (in the United States by
the Environmental Protection Agency [EPA]), particle filters or air-
cleaning devices having a MERV of not less than 13 when rated in
accordance with ASHRAE Standard 52.2 shall be provided to clean
outdoor air prior to its introduction to occupied spaces.
6.2.6.2 Ozone
In addition to ASHRAE Standard 62.1 Section 6.2.1.2 requirements, when the
building is located in an area that is designated 'non-attainment' with the
National Primary and Secondary Ambient Air Quality Standards for ozone
as determined by the AHJ (in the United States, by the EPA), air cleaner
cleaning devices having a removal efficiency of no less than the one effi-
ciency specified in ASHRAE Standard 62.1 Section 6.2.1.2 shall be provided
to clean outdoor air prior to its introduction to occupied spaces.
6.2.6.3 Bypass Pathways
All filter frames, air cleaner racks, access doors and air cleaner cartridges
shall be sealed to eliminate air bypass pathways.
6.2.7 Building Requirements
6.2.7.1 Building Entrances
All building entrances shall employ an entry mat system that shall have a
scraper surface, an absorption surface and a finishing surface. Each surface
shall be a minimum of the width of the entry opening, and the minimum