Page 192 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

170 Cha pte r F o u r

Special Circumstances and Exemplary Performance
EAc3 has been listed as a construction phase submittal, primarily because many of the
activities cannot be performed or verified until during or after substantial completion
of the project. It is also listed with the EB icon. The potential for many benefits associated
with a commissioning-type review process for system efficiencies that do not necessitate
substantial investment of additional monies for future retrofits is lost if not initiated in
the early phases of the initial project. There were no exemplary performance points
associated with this credit in LEED 2.2. In LEED 2009, an EP point may be obtained
based on comprehensive envelope commissioning being included.

4.4 EA Credit 4: Enhanced Refrigerant Management
As mentioned in EAp3, there is an effort internationally to reduce the use of certain
refrigerants and fire suppression chemicals that have negatively impacted the amount
of ozone in the stratosphere. The Montreal Protocol, as mentioned in the credit intent,
is the international agreement that sets timetables for the elimination of production and
reduction in use of many of these chemicals. Its full title is the Montreal Protocol on
Substances that Deplete the Ozone Layer. There is an international panel related to the
Montreal Protocol called the Technology and Assessment Panel (TEAP).
The intention of EA credit 4 is to reduce the use of refrigeration and fire suppression
chemicals that have a large ozone depletion potential (ODP), including many as listed
in the Montreal Protocol, while also considering the global warming potential (GWP) of
the alternatives. The global warming potential of a substance is an index that was
established by the International Panel on Climate Change (IPCC). LEED 2009 awards
two points for EAc4, whereas LEED 2.2 awarded one point.

USGBC Rating System
LEED-NC 2.2, as modified for verbiage in LEED 2009, lists the Intent, Requirements,
and Potential Technologies and Strategies for EAc4 as follows:

Intent
Reduce ozone depletion and support early compliance with the Montreal Protocol while
minimizing direct contributions to climate change.
Requirements
OPTION 1
Do not use refrigerants.
OR
OPTION 2
Select refrigerants and HVAC&R that minimize or eliminate the emission of compounds
that contribute to ozone depletion and global climate change. The base building HVAC&R
equipment shall comply with the following formula, which sets a maximum threshold for
the combined contributions to ozone depletion and global warming potential:
LCGWP = LCODP × 100,000 ≤ 100
Where:
LCODP = [ODPr × (Lr × Life + Mr) × Rc]/Life
LCGWP = [GWPr × (Lr × Life + Mr) × Rc]/Life
LCODP: Lifecycle Ozone Depletion Potential (lbCFC /Ton-Year)
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