The commercial building project shall comply with the requirements in Sections 502 (Building envelope requirements), 503 (Building mechanical systems), 504 (Service water heating) and 505 (Electrical power and lighting systems) in its entirety.
When heated slabs are placed belowgrade, below-gradewalls must meet the
exterior insulation requirements for perimeter insulation according to the
heated slab-on-grade construction.
An assembly with a U-factor, C-factor, or F-factor equal or less than that specified in Table 502.1.2 shall be permitted as an alternative to the R-value in Table
502.1.1.Commercial buildings or portions of commercial buildings enclosing Group R occupancies shall use the U-factor, C-factor, or F-factor from the "Group R" column of Table 502.1.2. Commercial buildings or portions of commercial buildings enclosing occupancies other than Group R shall use the U-factor, C-factor or F-factor from the "All other" column of Table 502.1.2.
Appendix A
of ASHRAE 90.1-2010 shall be used for determining values
for opaque assemblies.
TABLE 502.1.2
BUILDING ENVELOPE REQUIREMENTS
OPAQUE ELEMENT, MAXIMUM U-FACTORS
When heated slabs are placed below-grade, belowgradewalls must meet the
F-factor requirements for perimeter insulation according to the heated
slab-on-grade construction.
Exception: Integral insulated concrete block walls complying with ASTM
C90 with all cores filled and meeting both of the following: 1) At least 50 percent
of cores must be filledwith vermiculite or equivalent fill insulation, and 2)
the structure encloses one of the following uses: gymnasiums, auditorium,
church chapel, arena, kennel, manufacturing plant, indoor swimming pool,
pump station, water and waste water treatment facility, storage facility,
restroom/concessions, mechanical/electrical structures, storage area, warehouse
(storage and retail), motor vehicle service facility.
R-3.5 spacer blocks required for all metal roof assemblies; see Table
502.2(2).
Buildings may
demonstrate compliance with the thermal performance
standards of this section by using the Simplified Trade-off
Approach (STA). The STA is an analytical method to determine
if the energy performance of a proposed building's
envelope is at least equivalent to a similar building meeting
the prescriptive path approach. Information and criteria for
demonstrating compliance using the STA path using
COMcheck software is available at www.bcd.oregon.gov.
Standing seam roof with single fiberglass insulation layer.
This construction is R-19 faced fiberglass insulation batts draped perpendicular over the purlins. A minimum R-3.5 thermal spacer block is placed above the purlin/batt, and the roof deck is secured to the purlins.
R-13 + R-13 R-13 + R-19
Standing seam roof with two fiberglass insulation layers.
The first R-value is for faced fiberglass insulation batts draped over purlins. The second R-value is for unfaced fiberglass insulation batts installed parallel to the purlins. A minimum R-3.5 thermal spacer block is placed above the purlin/batt, and the roof deck is secured to the purlins.
WALLS
R-13 + R-5.6 ci R-19 + R-5.6 ci
The first R-value is for faced fiberglass insulation batts installed perpendicular and compressed between the metal wall panels and the steel framing. The second rated R-value is for continuous rigid insulation installed between the metal wall panel and steel framing, or on the interior of the steel framing.
The minimum thermal resistance (R-value) of the insulating material installed either between the roof framing or continuously on the roof assembly shall be as specified in Table 502.2(1), based on construction materials used in the roof assembly.
Exception:Continuously insulated roof assemblies where the thickness of insulation varies 1 inch (25 mm) or less and where the area-weighted U-factor is equivalent to the same assembly with the R-value specified in Table 502.2(1).
Insulation installed on a suspended ceiling with removable ceiling tiles shall not be considered part of the minimum thermal resistance of the roof insulation.
Above-grade walls are those walls covered by Section 502.2.3 on the exterior of the building and completely above grade or walls that are more than 15 percent above grade.
Below-grade walls covered by Section 502.2.4 are basement or first-story walls associated with the exterior of the building that are at least 85 percent below grade.
The minimum thermal resistance (R-value) of the insulating material(s) installed in the wall cavity between the framing members and continuously on the walls shall be as specified in Table
502.1.1, based on framing type and construction materials used in the wall assembly. The R-value of integral insulation installed in concrete masonry units (CMU) shall not be used in determining compliance with Table
502.1.1. "Mass walls" shall include walls weighing at least (1) 35 pounds per square foot (170 kg/m2) of wall surface area or (2) 25 pounds per square foot (120 kg/m2) of wall surface area if the material weight is not more than 120 pounds per cubic foot (1900 kg/m3).
The minimum thermal resistance (R-value) of the insulating material installed in, or continuously on, the below-grade walls shall be as specified in Table
502.1.1, and shall extend to a depth of 10 feet (3048 mm) below the outside finished ground level, or to the level of the floor, whichever is less.
The minimum thermal resistance (R-value) of the insulating material installed either between the floor framing or con-tinuously on the floor assembly shall be as specified in Table
502.1.1, based on construction materials used in the floor assembly.
"Mass floors" shall include floors weighing at least (1) 35 pounds per square foot (170 kg/m2) of floor surface area or (2) 25 pounds per square foot (120 kg/m2) of floor surface area if the material weight is not more than
120 pounds per cubic foot (1,900 kg/m3).
The minimum thermal resistance (R-value) of the insulation around the perimeter of unheated or heated slab-on-grade floors shall be as specified in Table
502.1.1. The insulation shall be placed on the outside of the foundation or on the inside of a foundation wall. The insulation shall extend downward from the top of the slab for a minimum distance as shown in the table or to the top of the footing, whichever is less, or downward to at least the bottom of the slab and then horizontally to the interior or exterior for the total distance shown in the table.
Opaque doors (doors having less than 50 percent glass area) shall meet the applicable requirements for doors as specified in Table
502.1.1 and be considered as part of the gross area of above-grade walls that are part of the building envelope.
The vertical fenestration area (not including opaque doors) shall not exceed the percentage of the gross wall area specified in Table 502.3. The skylight area shall not exceed the percentage of the gross roof area specified in Table 502.3.
A continuous air barrier shall be provided
throughout the building thermal envelope. The air
barriers shall be permitted to be located on the inside or outside
of the building envelope, located within the assemblies
composing the envelope, or any combination thereof. The
air barrier shall comply with Sections 502.4.1.1 and
502.4.1.2.
The continuous air
barrier shall be constructed to comply with the following:
The air barrier shall be continuous for all assemblies
that are the thermal envelope of the building
and across the joints and assemblies.
Air barrier joints and seams shall be sealed, including
sealing transitions in places and changes in
materials. Air barrier penetrations shall be sealed
in accordance with Section C502.4.2. The joints
and seals shall be securely installed in or on the
joint for its entire length so as not to dislodge,
loosen or otherwise impair its ability to resist positive
and negative pressure from wind, stack effect
and mechanical ventilation.
Recessed lighting fixtures shall comply with Section
504.2.8. Where similar objects are installed
which penetrate the air barrier, provisions shall be
made to maintain the integrity of the air barrier.
Exception: Buildings that comply with Section
502.4.1.2.3 are not required to comply with Items 1
and 3.
Materials with an air permeability
no greater than 0.004 cfm per square foot (0.02
L/s • m2) under a pressure differential of 0.3 inches
water gauge (w.g.) (75 Pa) when tested in accordance
with ASTM E 2178 shall comply with this section.
Materials in Items 1 through 15 shall be deemed to
comply with this section provided joints are sealed
and materials are installed as air barriers in accordance
with the manufacturer's instructions:
Plywood with a thickness of not less than 3/8
inch (10 mm).
Orientated strand board having a thickness of
not less than 3/8 inch (10 mm).
Extruded polystyrene insulation board having
a thickness of not less than 1/2 inch (12 mm).
Foil-back polyisocyanurate insulation board
having a thickness of not less than 1/2 inch (12
mm).
Closed-cell spray foam with a minimum density
of 1.5 pcf (2.4 kg/m3) having a thickness
of not less than 1 1/2 inches (36 mm).
Open-cell spray foam with a density between
0.4 and 1.5 pcf (0.6 and 2.4 kg/m3) and having
a thickness of not less than 4.5 inches (113
mm).
Exterior or interior gypsum board having a
thickness of not less than 1/2 inch (12 mm).
Cement board having a thickness of not less
than 1/2 inch (12 mm).
Built-up roofing membrane.
Modified bituminous roof membrane.
Fully adhered single-ply roof membrane.
A Portland cement/sand parge, or gypsum
plaster having a thickness of not less than 5/8
inch (16 mm).
Assemblies of materials and
components with an average air leakage not to exceed
0.04 cfm per square foot (0.2 L/s • m2) under a pressure
differential of 0.3 inches of water gauge
(w.g.)(75 Pa) when tested in accordance with ASTM
E 2357, ASTM E 1677 or ASTM E 283 shall comply
with this section. Assemblies listed in Items 1 and 2
shall be deemed to comply provided joints are sealed
and requirements of Section C502.4.1.1 are met.
Concrete or masonry walls coated with one
application either of block filler and two applications
of a paint, or sealer coating.
A Portland cement/sand parge, stucco or plaster,
minimum 1/2 inch (12 mm) in thickness.
The completed building
shall be tested and the air leakage rate of the building
envelope shall not exceed 0.40 cfm per square foot at a
pressure differential of 0.3 inches water gauge (2.0
L/s • m2 at 75 Pa) in accordance with ASTM E 779 or
an equivalent method approved by the code official.
Penetrations of the air
barrier and paths of air leakage shall be caulked, gasketed
or otherwise sealed in a manner compatible with the construction
materials and location. Joints and seals shall be
sealed in the same manner or taped or covered with a
moisture vapor-permeable wrapping material. Sealing
materials shall be appropriate to the construction materials
being sealed. The joints and seals shall be securely
installed in or on the joint for its entire length so as not to
dislodge, loosen or otherwise impair its ability to resist
positive and negative pressure from wind, stack effect
and mechanical ventilation.
The air
leakage of fenestration assemblies and doors and access
openings from conditioned space to shafts, chutes, stairways
and elevator lobbies shall meet the provisions of Table
502.4.3. Testing shall be in accordance with the applicable
reference test standard in Table 502.4.3 by an accredited,
independent testing laboratory and labeled by the manufacturer.
Fenestration in buildings that comply with Section
502.4.1.2.3 are not required to meet the air leakage
requirements in Table 502.4.3.
Doors and access panels that are continuously
gasketed, weatherstripped or sealed.
Door openings required to comply with Section
714 or 715.4 of the Building Code; or doors and
door openings required by the Building Code to
comply with UL 1784.
Stair and elevator shaft vents and other
ventilation openings integral to the building envelope shall be equipped with not less than a Class I motorized, leakage-rated damper with a maximum leakage rate of 4 cfm per square foot (6.8 L/s • C m2) at 1.0 inch water gauge (w.g.) (1250 Pa) when tested in accordance with AMCA 500D.
Stair and shaft vent dampers shall be capable of being
automatically closed during normal building operation and
interlocked to open as required by the Building Code.
Exceptions:
Mechanical systems intake, exhaust and relief
openings shall comply with Section 503.2.4.5.
Elevator shaft vents complying with the Oregon
Elevator Specialty Code.
A door that separates conditioned space from the exterior shall be protected with an enclosed vestibule, with all doors opening into and out of the vestibule equipped with self-closing devices. Vestibules shall be designed so that in passing through the vestibule it is not necessary for the interior and exterior doors to open at the same time.
Exceptions:
Doors not intended to be used as a building entrance door, such as doors to mechanical or electrical equipment rooms.
Recessed luminaires installed in the building thermal envelope shall be sealed to limit air leakage between conditioned and unconditioned spaces. All recessed luminaires shall be IC-rated and labeled as meeting ASTM E 283 when tested at 1.57 psf (75 Pa) pressure differential with no more than 2.0 cfm (0.944 L/s) of air movement from the conditioned space to the ceiling cavity. All recessed luminaires shall be sealed with a gasket or caulk between the housing and interior wall or ceiling covering.
Mechanical systems and equipment serving the building heating, cooling or ventilating needs shall comply with Section 503.2 (referred to as the mandatory provisions) and either:
Design loads shall be determined in accordance with the procedures described in the ASHRAE/ACCA Standard 183. Heating and cooling loads shall be adjusted to account for load reductions that are achieved when energy recovery systems are utilized in the HVAC system in accordance with the ASHRAE HVAC Systems and Equipment Handbook. Alternatively, design loads shall be determined by an approved equivalent computation procedure, using the design parameters specified in Chapter 3.
Forced air unit
and packaged electric equipment with a total heating
capacity greater than 20,000 Btu/h (5862W) shall have a
heat pump as the primary heating source.
Exception: Unstaffed equipment shelters or cabinets
used solely for personal wireless service facilities.
Equipment and system sizing. Heating and cooling equipment and systems capacity shall not exceed the loads calculated in accordance with Section 503.2.1. A single piece of equipment providing both heating and cooling must satisfy this provision for one function with the capacity for the other function as small as possible, within available equipment options.
Exceptions:
Required standby equipment and systems provided with controls and devices that allow such systems or equipment to operate automatically only when the primary equipment is not operating.
Multiple units of the same equipment type with combined capacities exceeding the design load and provided with controls that have the capability to sequence the operation of each unit based on load.
Equipment shall meet the minimum efficiency requirements of Tables 503.2.3(1), 503.2.3(2), 503.2.3(3), 503.2.3(4), 503.2.3(5), 503.2.3(6), 503.2.3(7), 503.2.3(8), 503.2.3(9) and 503.2.3(10) when tested and rated in accordance with the applicable test procedure. The efficiency shall be verified through certification under an approved certification program or, if no certification program exists, the equipment efficiency ratings shall be supported by data furnished by the manufacturer. Where multiple rating conditions or performance requirements are provided, the equipment shall satisfy all stated requirements. Where components, such as indoor or outdoor coils, from different manufacturers are used, calculations and supporting data shall be furnished by the designer that demonstrates that the combined efficiency of the specified components meets the requirements herein.
TABLE 503.2.3(1) MINIMUM EFFICIENCY REQUIREMENTS: ELECTRICALLY OPERATED UNITARY AIR CONDITIONERS AND CONDENSING UNITS
"Cap" = The rated cooling capacity of the project in Btu/h. If the unit's capacity is less than 7000 Btu/h, use 7000 Btu/h in the calculation. If the unit's capacity is greater than 15,000 Btu/h, use 15,000 Btu/h in the calculations.
Chapter 6 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure.
Replacement unit shall be factory labeled as follows: "MANUFACTURED FOR REPLACEMENT APPLICATIONS ONLY: NOT TO BE INSTALLED IN NEWCONSTRUCTION PROJECTS." Replacement efficiencies apply only to units with existing sleeves less than 16 inches (406 mm) in height and less than 42 inches (1067 mm) in width.
TABLE 503.2.3(4) WARM AIR FURNACES AND COMBINATION WARM AIR FURNACES/AIR-CONDITIONING UNITS, WARM AIR DUCT FURNACES AND UNIT HEATERS, MINIMUM EFFICIENCY REQUIREMENTS
Chapter 6 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure.
Minimum and maximum ratings as provided for and allowed by the unit's controls.
Combination units not covered by the National Appliance Energy Conservation Act of 1987 (NAECA) (3-phase power or cooling capacity greater than or equal to 65,000 Btu/h [19 kW]) shall comply with either rating.
Et = Thermal efficiency. See test procedure for detailed discussion.
Ec = Combustion efficiency. Units shall also include an IID, have jackets not exceeding 0.75 percent of the input rating, and have either power venting or a flue damper. A vent damper is an acceptable alternative to a flue damper for those furnaces where combustion air is drawn from the conditioned space.
Et = Thermal efficiency. Units shall also include an IID, have jacket losses not exceeding 0.75 percent of the input rating, and have either power venting or a flue damper. A vent damper is an acceptable alternative to a flue damper for those furnaces where combustion air is drawn from the conditioned space.
TABLE 503.2.3(5) MINIMUM EFFICIENCY REQUIREMENTS: GAS- AND OIL-FIRED BOILERS
For SI: 1 British thermal unit per hour = 0.2931 W. Ec = Combustion efficiency (100 percent less flue losses). Et = Thermal efficiency. See referenced standard for detailed information.
These requirements apply to boilers with rated input of 8,000,000 Btu/h or less that are not packaged boilers and to all packaged boilers. Minimum efficiency requirements for boilers cover all capacities of packaged boilers.
Maximum capacity — minimum and maximum ratings as provided for and allowed by the unit's controls.
The requirements for centrifugal chiller shall be adjusted for nonstandard rating conditions in accordance with Section 503.2.3.1 and are only applicable for the range of conditions listed in Section 503.2.3.1. The requirements for air-cooled,water-cooled positive displacement and absorption chillers are at standard rating conditions defined in the reference test procedure.
Both the full load and IPLV requirements shall be met or exceeded to comply with this code. Where there is a Path B, compliance can be with either Path A or Path B for any application.
FL is the full load performance requirements and IPLV is for the part load performance requirements.
NA means the requirements are not applicable for Path B and only Path A can be used for compliance.
For SI: °C = [(°F)-32]/1.8, L/s • kW = (gpm/hp)/(11.83), COP = (Btu/h • hp)/(2550.7), db = dry bulb temperature, °F, wb = wet bulb temperature, °F.
The efficiencies and test procedures for both open and closed circuit cooling towers are not applicable to hybrid cooling towers that contain a combination of wet and dry heat exchange sections.
For purposes of this table, open circuit cooling tower performance is defined as the water flow rating of the tower at the thermal rating condition listed in Table 403.2.3(8) divided by the fan nameplate rated motor power.
For purposes of this table, closed circuit cooling tower performance is defined as the water flow rating of the tower at the thermal rating condition listed in Table 403.2.3(8) divided by the sum of the fan nameplate rated motor power and the spray pump nameplate rated motor power.
For purposes of this table, air-cooled condenser performance is defined as the heat rejected from the refrigerant divided by the fan nameplate rated motor power.
Chapter 6 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure. The certification requirements do not apply to field erected cooling towers.
Where a certification program exists for a covered product, and it includes provisions for verification and challenge of equipment efficiency ratings, then the product shall be listed in the certification program, or, where a certification program exists for a covered product, and it includes provisions for verification and challenge of equipment efficiency ratings, but the product is not listed in the existing certification program, the ratings shall be verified by an independent laboratory test report.
All cooling towers shall comply with the minimum efficiency listed in the table for that specific type of tower with the capacity effect of any project specific accessories and /or options included in the capacity of the cooling tower.
For purposes of this table, evaporative condenser performance is defined as the heat rejected at the specified rating condition in the table divided by the sum of the fan motor nameplate power and the integral spray pump nameplate power.
Requirements for evaporative condensers are listed with ammonia (R-717) and R-507A as test fluids in the table. Evaporative condensers intended for use with halocarbon refrigerants other than R-507A shall meet the minimum efficiency requirements listed above with R-507A as the test fluid.
TABLE 503.2.3(9) MINIMUM EFFICIENCY AIR CONDITIONERS AND CONDENSING UNITS SERVING COMPUTER ROOMS
EQUIPMENT TYPE
NET SENSIBLE COOLING CAPACITYa
MINIMUMSCOP-127b EFFICIENCY DOWNFLOW UNITS/UPFLOW UNITS
Net sensible cooling capacity: The total gross cooling capacity less the latent cooling less the energy to the air movement system. (Total Gross — latent — Fan Power).
Sensible coefficient of performance (SCOP-127): a ratio calculated by dividing the net sensible cooling capacity in watts by the total power input in watts (excluding reheaters and humidifiers) at conditions defined in ASHRAE Standard 127. The net sensible cooling capacity is the gross sensible capacity minus the energy dissipated into the cooled space by the fan system.
Equipment not designed for operation at AHRI
Standard 550/590 test conditions of 44°F (7°C) leaving
chilled-water temperature and 2.4 gpm/ton evaporator
fluid flow and 85°F (29°C) entering condenser water
temperature with 3 gpm/ton (0.054 I/s • kW) condenser
water flow shall have maximum full-load kW/ton (FL)
and part load ratings requirements adjusted using Equations
4-5 and 4-6.
The supply of heating and cooling energy to each zone shall be controlled by individual thermostatic controls
that respond to temperature
within the zone.
Exception: Independent perimeter systems that are designed to offset only building envelope heat losses or gains or both serving one or more perimeter zones also served by an interior system provided:
The perimeter system includes at least one ther-mostatic control zone for each building expo-sure having exterior walls facing only one orientation (within +/- 45 degrees) (0.8 rad) for more than 50 contiguous feet (15.2 m); and
The perimeter system heating and cooling sup-ply is controlled by a thermostat(s) located within the zone(s) served by the system.
Heat pumps having supplementary electric resistance heat shall have controls that, except during defrost, prevent supplementary heat operation when the heat pump can meet the heating load.
Where used to control both heating and cooling, zone thermostatic controls shall provide a temperature range or deadband of at least 5°F (2.8°C) within which the supply of heating and cooling energy to the zone is capable of being shut off or reduced to a minimum.
Exception:Thermostats requiring manual changeover between heating and cooling modes.
Automatic time clock or programmable controls shall be capable of starting and stopping the system for seven different daily schedules per week and retaining their programming and time setting during a loss of power for at least 10 hours. Additionally, the controls shall have a manual override that allows temporary operation of the system for up to 2 hours; a manually operated timer capable of being adjusted to operate the system for up to 2 hours; or an occupancy sensor.
Outdoor air
supply exhaust and relief shall be equipped with not less
than Class I motorized dampers with a maximum leakage
rate of 4 cfm per square foot (6.8 L/s • C m2) at 1.0
inch water gauge (w.g.) (1250 Pa) when tested in accordance with AMCA 500D, that will automatically shut
when the systems or spaces served are not in use.
Exceptions:
Gravity dampers shall be permitted for outside air intake or exhaust airflows of 300 cfm (0.14 m3/s) or less.
Relief dampers integral to packaged cooling
equipment.
Freeze protection systems, such as heat tracing
of outdoor piping and heat exchangers, including
self-regulating heat tracing, shall include automatic controls
capable of shutting off the systems when outdoor
air temperatures are above 40°F (4°C) or when the conditions
of the protected fluid will prevent freezing.
Snow- and ice-melting systems, supplied through energy service to the building, shall include automatic controls capable of shutting off the system when the pavement temperature is above 50°F (10°C) and no precipitation is falling and an automatic or manual control that will allow shutoff when the outdoor temperature is above 40°F (4°C) so that the potential for snow or ice accumulation is negligible.
A system serving
multiple occupancies or floors in the same building shall
be independently zoned and equipped with isolation
devices capable of automatically shutting off the supply
of conditioned air and outside air to and from each isolated
area. Each isolated area shall be controlled independently
and satisfy temperature setback (see Section
503.2.4.4.1) and optimum start control requirements
(see Section 503.2.4.3). The central fan system air volume
shall be reduced through fan speed reduction.
Exception: A cooling system less than 240,000 Btu/h
(70 kW) or a heating system with less than 300,000
Btu/h (88 kW) total capacity.
Zones
with special process temperature requirements and/or
humidity requirements shall be served by separate air
distribution systems from those serving zones requiring
only comfort conditions; or shall include supplementary
control provisions so that the primary systems may be
specifically controlled for comfort purposes only.
Exceptions: Zones requiring only comfort heating or
comfort cooling that are served by a system primarily
used for process temperature and humidity control
provided that:
The total supply air to those comfort zones is no
more than 25 percent of the total system supply
air, or
If a system is equipped
with a means to add or remove moisture to maintain specific
humidity levels in a zone or zones, a humidity control
device shall be provided.
The humidity control device shall be set to
prevent the use of fossil fuel or electricity to produce
relative humidity in excess of 30 percent. Where a
humidity control device is used for dehumidification, it
shall be set to prevent the use of fossil fuel or electricity
to reduce relative humidity below 60 percent.
Exception: Hospitals, process needs, archives,
museums, critical equipment, and other
noncomfort situations with specific humidity
requirements outside this range.
Humidity controls shall maintain a
deadband of at least 10 percent relative humidity where
no active humidification or dehumidification takes
place.
Exception: Heating for dehumidification is provided
with heat recovery or heat pumping and the
mechanical cooling system efficiency is 10 percent
higher than required in Section 503.2.3, HVAC
equipment performance requirements.
Ventilation, either natural or mechanical, shall be provided in accordance with Chapter 4 of the
Mechanical Code. Where mechanical ventila-tion is provided, the system shall provide the capability to reduce the outdoor air supply to the minimum required by Chapter 4 of the
Mechanical Code.
Demand control ventilation (DCV) is required for spaces with an average occupant load of 25 people or more per 1000 square feet (93 m2) of floor area (as established in Table 403.3 of the Mechanical Code) and served by systems with one or more of the following:
An air-side economizer;
Automatic modulating control of the outdoor air damper; or
A design outdoor airflow greater than 3,000 cfm (1400 L/s).
Exceptions:
Spaces smaller than 500 square feet (46.5 m2) served by single-zone systems.
Spaces smaller than 150 square feet (13.9 m2) served by multiple-zone systems.
Systems with energy recovery complying with Section 503.2.6.
Spaces less than 750 square feet (69.7 m2) where an occupancy sensor turns the fan off, closes the ventilation damper, or closes the zone damper when the space is unoccupied.
Kitchen makeup air shall be
provided as required by the Mechanical Code. For each
kitchen with a total exhaust capacity greater than 5,000
cfm (2360 L/s), 50 percent of the required makeup air
shall be (a) unheated or heated to no more than 60°F
(15.55°C); and (b) uncooled or evaporatively cooled.
Exception: Where hoods are used to exhaust ventilation
air that would otherwise be exhausted by other
fan systems. Air transferred from spaces served by
other fan systems may not be used if those systems are
required to meet either Sections 503.2.5.1 or 503.2.6.
Occupancy schedule of HVAC system supplying
transfer air shall be similar to kitchen exhaust hood
operating schedule.
Each kitchen
with a total Type 1 exhaust capacity greater than 5,000
cfm (2360 L/s) shall be equipped with a demand ventilation
system on at least 75 percent of the exhaust
and makeup air. Such systems shall be equipped with
automatic controls that reduce airflow in response to
cooking appliance operation.
In Group S-2, enclosed parking garages used for
storing or handling automobiles operating under their
own power having ventilation exhaust rates 30,000 cfm
(14 157 L/s) and greater shall employ automatic carbon
monoxide sensing devices. These devices shall modulate
the ventilation system to maintain a maximum average
concentration of carbon monoxide of 50 parts per million
during any 8-hour period, with a maximum concentration
not greater than 200 parts per million for a period not
exceeding 1 hour. The system shall be capable of producing
a ventilation rate of 0.75 cfm per square foot (0.0038
m3/s • m2) of floor area. Failure of such devices shall
cause the exhaust fans to operate in the ON position.
Individual fan systems that have both a design supply air capacity of 5,000 cfm (2.36 m3/s) or greater and a minimum outside air supply of 70 percent or greater of the design supply air quantity shall have an energy recovery system that provides a change in the enthalpy of the outdoor air supply of 50 percent or more of the difference between the outdoor air and return air at design conditions. Provision shall be made to bypass or control the energy recovery system to permit cooling with outdoor air where cooling with outdoor air is required. Where a single room or space is supplied by multiple units, the aggregate supply (cfm) of those units shall be used in applying this requirement.
Where energy recovery systems are prohibited by the Mechanical Code.
Laboratory fume hood systems that include at least one of the following features:
Variable-air-volume hood exhaust and room supply systems that reduce exhaust and makeup air volume to 50 percent or less of design values during periods of reduced occupancy or system demand.
Variable-air-volume hood exhaust and room supply systems that reduce exhaust and makeup air volume and/or incorporate a heat recovery system to precondition makeup air from laboratory exhaust shall meet the following:
A + B*(E/M) = 50% where:
A
=
Percentage that the exhaust and makeup airflow rates will be reduced from design conditions.
B
=
Percentage sensible heat recovery effectiveness.
E
=
Exhaust airflow rate through the heat recovery device at design conditions.
M
=
Makeup air flowrate of the system at design conditions.
Direct makeup (auxiliary) air supply equal to at least 75 percent of the exhaust rate, heated no warmer than 2°F (1.1°C) below room setpoint, cooled to no cooler than 3°F (1.7°C) above room setpoint, no humidification added, and no simultaneous heating and cooling used for dehumidification control.
Systems serving spaces that are not cooled and are heated to less than 60°F (15.5°C).
Where more than 60 percent of the outdoor heating energy is provided from site-recovered or site solar energy.
Type 1 kitchen exhaust hoods.
Cooling systems in climates with a 1-percent cooling design wet-bulb temperature less than 64°F (18°C).
Systems requiring dehumidification that employ series-style energy recovery coils wrapped around the cooling coil when the evaporative coil is located upstream of the exhaust air stream.
Systems exhausting toxic, flammable, paint exhaust, corrosive fumes or dust.
All supply and return air ducts and plenums shall be insulated with a minimum of R-5 insulation when located in unconditioned spaces and a minimum of R-8 insulation when located outside the building. When located within a building envelope assembly, the duct or plenum shall be separated from the building exterior or unconditioned or exempt spaces by a minimum of R-8 insulation.
Exceptions:
When located within equipment.
When the design temperature difference between the interior and exterior of the duct or plenum does not exceed 15°F (8°C).
All ducts, air handlers and filter boxes shall be sealed. Joints and seams shall comply with Section 603.9 of the Mechanical Code.
All longitudinal and transverse joints, seams and connections of supply and return ducts operating at a static pressure less than or equal to 2 inches w.g. (500 Pa) shall be securely fastened and sealed with welds, gaskets, mastics (adhesives), mastic-plus-embedded-fabric systems or tapes installed in accordance with the manufacturer's installation instructions. Pressure classifications specific to the duct system shall be clearly indicated on the construction documents in accordance with the
Mechanical Code.
Exception: Continuously welded and locking-type longitudinal joints and seams on ducts operating at static pressures less than 2 inches w.g. (500 Pa) pressure classification.
All ducts and plenums designed to operate at a static pressure greater than 2 inches w.g. (500 Pa) but less than 3 inches w.g. (750 Pa) shall be insulated and sealed in accordance with Section 503.2.7. Pressure classifications specific to the duct system shall be clearly indicated on the construction documents in accordance with the
Mechanical Code.
Ducts designed to operate at static pressures in excess of 3 inches w.g. (746 Pa) shall be insulated and sealed in accordance with Section 503.2.7. In addition, ducts and plenums shall be leak-tested in accordance with the SMACNA HVAC Air Duct Leakage Test Manual with the rate of air leakage (CL) less than or equal to 6.0 as determined in accordance with
Equation 5-3.
CL = F × P0.65
(Equation 5-3.)
where:
F = The measured leakage rate in cfm per 100 square feet of duct surface.
P = The static pressure of the test.
Documentation shall be furnished by the designer demonstrating that representative sections totaling at least 25 percent of the duct area have been tested and that all tested sections meet the requirements of this section.
All piping serving as part of a heating or cooling system shall be thermally insulated in accordance with Table 503.2.8.
Exceptions:
Factory-installed piping within HVAC equipment tested and rated in accordance with a test procedure referenced by this code.
Factory-installed piping within room fan-coils and unit ventilators tested and rated according to AHRI 440 (except that the sampling and variation provisions of Section 6.5 shall not apply) and 840, respectively.
Piping that conveys fluids that have a design operating temperature range between
60°F (14°C) and 105°F (41°C).
Piping that conveys fluids that have not been heated or cooled through the use of fossil fuels or electric power.
Runout piping not exceeding 4 feet (1219 mm) in length and 1 inch (25 mm) in diameter between the control valve and HVAC coil.
TABLE 503.2.8
MINIMUM PIPE INSULATION THICKNESS (thickness in inches)a, b, c
For piping smaller than 11/2 inch (38 mm) and located in partitions within conditioned spaces, reduction of these thicknesses by 1 inch (25 mm) shall be permitted (before thickness adjustment required in footnote b) but not to a thickness less that 1 inch (25 mm).
For insulation outside the stated conductivity range, the minimum thickness (T) shall be determined as follows:
T = r {(1 + t/r )K/k — 1}
where:
T
=
minimum insulation thickness,
r
=
actual outside radius of pipe,
t
=
insulation thickness listed in Table 503.2.8 for applicable fluid temperature and pipe size,
K
=
conductivity of alternate material at mean rating temperature indicated for the applicable fluid temperature (Btu× in./h x ft2 × °F) and
k
=
uppper value of the conductivity range listed in the table for the applicable fluid temperature.
For direct-buried heating and hot water system piping, reduction of these thicknesses by 11/2 inches (38 mm) shall be permitted (before thickness adjustment required in footnote b but not to thicknesses less than 1 inch (25 mm).
Piping insulation
exposed to weather shall be protected from damage,
including that due to sunlight, moisture, equipment
maintenance, and wind, and shall provide shielding from solar radiation that can cause degradation of the material.
Adhesives tape shall not be permitted as the means of
protection and shall be used in accordance with manufacturer's
specfications.
Each supply air outlet and zone terminal device shall be equipped with means for air balancing in accordance with the requirements of Chapter 6 of the
Mechanical Code. Discharge dampers
intended to modulate airflow are prohibited on constant volume fans and variable volume fans with motors 10 horsepower (hp)
(7.5 kW) and larger.
The construction documents shall require that an operating and maintenance manual be provided to the building owner by the mechanical contractor. The manual shall include, at least, the following:
Equipment capacity (input and output) and required maintenance actions.
HVAC system control maintenance and calibration information, including wiring diagrams, schematics, and control sequence descriptions. Desired or field-determined setpoints shall be permanently recorded on control drawings, at control devices or, for digital control systems, in programming comments.
A complete written narrative of how each system is intended to operate.
Each HVAC system having a total fan system motor nameplate horsepower (hp) exceeding 5 horsepower (hp)
(3.7 kW) shall meet the provisions of Sections 503.2.10.1 through 503.2.10.2.
Each HVAC system at fan system design conditions shall not exceed the allowable fan system motor nameplate hp (Option 1) or fan system bhp (Option 2) as shown in Table 503.2.10.1(1). This includes supply fans, return/relief fans, and fan-powered terminal units associated with systems providing heating or cooling capability.
Laboratory and vivarium exhaust systems in high-rise buildings
0.25 in. w.c./100 ft. of vertical duct exceeding 75 feet
For SI: 1 foot = 304.8 mm.
Exceptions:
Hospital and laboratory systems that utilize flow control devices on exhaust and/or return to maintain space pressure relationships necessary for occupant health and safety or environmental control shall be permitted to use variable volume fan power limitation.
Individual exhaust fans with motor nameplate horsepower of 1 hp (0.7 kW) or less.
For each fan, the selected fan motor shall be no larger than the first available motor size greater than the brake horsepower (bhp). The fan brake horsepower (bhp) shall be indicated on the design documents to allow for compliance verification by the code official.
Exceptions:
For fans less than 6 bhp, where the first available motor larger than the brake horsepower has a nameplate rating within 50 percent of the bhp, selection of the next larger nameplate motor size is allowed.
For fans 6 bhp and larger, where the first available motor larger than the bhp has a nameplate rating within 30 percent of the bhp, selection of the next larger nameplate motor size is allowed.
Large volume
fan systems shall comply with Sections 503.2.10.3.1 and
503.2.10.3.2 as applicable.
Exception: Systems where the function of the supply
air is for purposes other than temperature control,
such as maintaining specific humidity levels or supplying
an exhaust system
Fan systems over 8,000 cfm (7 m3/s)
without direct expansion cooling coils that serve single
zones are required to reduce airflow based on
space thermostat heating and cooling demand. A
two-speed motor or variable frequency drive shall
reduce airflow to a maximum 60 percent of peak airflow
or minimum ventilation air requirement as
required by Chapter 4 of the Mechanical Code,
whichever is greater.
All air-conditioning equipment and
air-handling units with direct expansion cooling and a
cooling capacity at AHRI conditions greater than or
equal to 110,000 Btu/h (32241W) that serve single
zones shall have their supply fans controlled by
two-speed motors or variable speed drives. At cooling
demands less than or equal to 50 percent, the supply
fan controls shall be able to reduce the airflow to no
greater than the larger of the following:
Two-thirds of the full fan speed, or
The volume of outdoor air required to meet the
ventilation requirements of Standard 62.1.
Fan motors for series fan-powered terminal
units shall be electronically-commutated motors and
have a minimum motor efficiency of 70 percent when
rated in accordance with NEMA Standard MG 1-2006 at
full load rating conditions.
Systems installed to provide heat outside a building shall be
infrared radiant systems. Such heating systems shall be controlled by an occupancy sensing device or a timer switch, so that the system is automatically deenergized when no occupants are present.
Infrared
spot heating meeting the control requirements of
Section 503.2.11 shall be allowed within unconditioned
and semiheated spaces without requiring the envelope to
comply as a conditioned space. Spot heating shall be limited
to the larger of 500 ft2 (m3) or 10 percent of the floor
area.
Cooling systems shall
not use hot gas bypass or other evaporator pressure control
systems unless the system is designed with multiple steps of
unloading or continuous capacity modulation. The capacity
of the hot gas bypass shall be limited as indicated in Table
503.2.12.
Exception: Unitary packaged systems with cooling
capacities not greater than 90,000 Btu/h (26379 W).
This section applies to
unitary or packaged HVAC equipment listed in Tables 503.2.3(1) through 503.2.3(5), each serving one zone and controlled by a single thermostat in the zone served. It also applies to two-pipe heating systems serving one or more zones, where no cooling system is installed.
This section does not apply to fan systems serving multiple zones, nonunitary or nonpackaged HVAC equipment and systems or hydronic or steam heating and hydronic cooling equipment and distribution systems that provide cooling or cooling and heating which are covered by Section 503.4.
Supply air economizers shall be provided on each cooling system and shall be capable of providing 100-percent outdoor air, even if additional mechanical cooling is required to meet the cooling load of the building. Systems shall provide a means to relieve excess outdoor air during economizer operation to prevent overpressurizing the building. The relief air outlet shall be located to avoid recirculation into the building. Where a single room or space is supplied by multiple air systems, the aggregate capacity of those systems shall be used in applying this requirement.
Exceptions:
Cooling equipment less than 54,000 Btu/h (15827 W) total cooling capacity. The total capacity of all such units without economizers shall not exceed 240,000 Btu/h (70342 W) per building area served by one utility meter or service, or 10 percent of its total installed cooling capacity, whichever is greater. That portion of the equipment serving dwelling units and guest rooms is not included in determining the total capacity of units without economizers.
Economizer cooling is not required for new cooling systems serving an existing dedicated computer server room, electronic equipment room or telecom switch room in existing buildings up to a total of 600,000 Btu/h (17586 W) of new cooling equipment.
Economizer cooling is not required for new cooling systems serving a new dedicated computer server room, electronic equipment room or telecom switch room in existing buildings up to a total of 240,000 Btu/h (70344 W) of new cooling equipment.
Hydronic systems of at least 300,000 Btu/h (87930W) design output capacity supplying heated
water to comfort conditioning systems shall include controls that meet the requirements of Section 503.4.3.
Supply air economizers shall be provided on each cooling system
and shall be capable of operating at 100 percent outside air, even if additional mechanical cooling is required to meet the cooling load of the building.
Exceptions:
Systems utilizing water economizers that are capable
of cooling supply air by direct or indirect evaporation
or both and providing 100 percent of the
expected system cooling load at outside air
temperatures of 50°F (10°C) dry bulb/45°F (7°C)
wet bulb and below
Cooling equipment less than 54,000 Btu/h (15827
W) total cooling capacity. The total capacity of all
such units without economizers shall not exceed
240,000 Btu/h (70342 W) per building area served
by one utility meter or service, or 10 percent of its
total installed cooling capacity, whichever is
greater. That portion of the equipment serving
dwelling units and guest rooms is not included in
determining the total capacity of units without
economizers.
Ground-coupled heat pumps with cooling capacity
of 54,000 Btu/h (15827 W) or less.
Systems where internal/external zone heat recovery
is used.
Systems used to cool any dedicated computer
server room, electronic equipment room or
telecom switch room having an economizer system
capable of cooling air by direct and/or indirect
evaporation and providing 100 percent of the
expected systems cooling load at outside air temperatures
of 45°F (7°C) dry bulb and 40°F (8°C)
wet bulb and below.
Economizer cooling is not required for new cooling
systems serving an existing dedicated computer
server room, electronic equipment room or
telecom switch room in existing buildings up to a
total of 600,000 Btu/h (175,800 W) of new cooling
equipment.
Economizer cooling is not required for new cooling
systems serving a new dedicated computer
server room, electronic equipment room or
telecom switch room in existing buildings up to a
total of 240,000 Btu/h (70,300 W) of new cooling
equipment.
Systems using condenser heat recovery, up to the
cooling capacity used to provide condenser heat
recovery.
Individual VAV fans with motors of 10 horsepower (7.5 kW) or greater shall be:
Driven by a mechanical or electrical variable speed drive; or
The fan motor shall have controls or devices that will result in fan motor demand of no more than 30 percent of their design wattage at 50 percent of design airflow when static pressure set point equals one-third of the total design static pressure, based on manufacturer's certified fan data.
For systems with direct digital control of individual zone boxes reporting to the central control panel, the static pressure set point shall be reset based on the zone requiring the most pressure, i.e., the set point is reset lower until one zone damper is nearly wide open.
The heating of fluids that have been previously mechanically cooled and the cooling of fluids that have been previously mechanically heated shall be limited in accordance with Sections 503.4.3.1 through 503.4.3.3. Hydronic heating systems comprised of multiple-packaged boilers and designed to deliver conditioned water or steam into a common distribution system shall include automatic controls capable of sequencing operation of the boilers. Hydronic heating systems comprised of a single boiler and greater than 500,000 Btu/h input design capacity shall include either a multistaged or modulating burner.
Systems that use a common distribution system to supply both heated and chilled water shall be designed to allow a dead band between changeover from one mode to the other of at least 15°F (8.3°C) outside air temperatures; be designed to and provided with controls that will allow operation in one mode for at least 4 hours before changing over to the other mode; and be provided with controls that allow heating and cooling supply temperatures at the changeover point to be no more than 30°F (16.7°C) apart.
Hydronic heat pumps connected to a common heat pump water loop with central devices for heat rejection and heat addition shall have controls that are capable of providing a heat pump water supply temperature dead band of at least 20°F (11.1°C) between initiation of heat rejection and heat addition by the central devices.
Exception: Where a system loop temperature optimization controller is installed and can determine the most efficient operating temperature based on realtime conditions of demand and capacity, dead bands of less than 20°F (11°C) shall be permitted.
Heat rejection equipment shall comply with this section.
If a closed-circuit cooling tower is used directly in
the heat pump loop, either an automatic valve shall
be installed to bypass all but a minimal flow of
water around the tower, or lower leakage positive
closure dampers shall be provided.
If an open-circuit tower is used directly in the heat
pump loop, an automatic valve shall be installed to
bypass all heat pump water flow around the tower.
If an open- or closed-circuit cooling tower is used
in conjunction with a separate heat exchanger to
isolate the cooling tower from the heat pump loop,
then heat loss shall be controlled by shutting down
the circulation pump on the cooling tower loop.
Exception: Where it can be demonstrated that a heat pump system will be required to reject heat throughout the year.
Each hydronic heat pump on the hydronic system having a total pump system power exceeding 10 horsepower (hp) (7.5 kW) shall have
an automatic two-position valve or be
served by a dedicated pump with check valve for each heat pump.
Hydronic systems greater than or equal to 300,000 Btu/h (87930W) in design output capacity supplying heated or chilled water to comfort conditioning systems shall include controls
that:
Automatically reset the supply-water tempera-
tures using zone-return water temperature,
building-return water temperature, or
outside air temperature as an indicator of building
heating or cooling demand. The temperature
shall be capable of being reset by at least 25
percent of the design supply-to-return water
temperature difference; or
For pumping systems less than 5hp (4 kW)
reduce system pump flow by at least 50 percent
of design flow rate utilizing adjustable speed
drive(s) on pump(s), or multiple-staged pumps
where at least one-half of the total pump horsepower
is capable of being automatically turned
off and control valves designed to modulate or
step down, and close, as a function of load, or
other approved means.
For pumping systems greater than 5hp (4 kW)
reduce system pump flow by at least 50 percent
of design flow rate utilizing adjustable speed
drive(s) on pump(s) and control valves
designed to modulate or step down, and close,
as a function of load, or other approved means.
Exception: Dedicated equipment circulation
pumps designed to meet minimum flow requirements
established by the manufacturer, such as
boiler or chiller auxiliary circulation pumps.
Chilled water plants including more than one chiller shall have the capability to reduce flow automatically through the chiller plant when a chiller is shut down. Chillers piped in series for the purpose of increased temperature differential shall be considered as one chiller.
Boiler plants including more than one boiler shall have the capability to reduce flow automatically through the boiler plant when a boiler is shut down.
Water circulation systems serving heating coil(s) or
cooling coil(s) shall have controls that lock out pump
operation when there is no demand. The pumps shall
shut off based on the following outside air lock out
temperatures: hot water pump whenever outside air
temperature is 70°F (21°C) or higher, cooling water
pump when outside air temperature is 55°F (13°C) or
lower.
Exceptions:
Industrial process and humidity control process,
Hot water reheat for terminal units,
Hot water circulation systems used to provide
multiple functions (e.g., space heating, service
water heating -DHW)as an integrated system.
Pumps serving water side economizer functions,
systems.
Open cooling towers
configured with multiple condenser water pumps
shall be designed so that all cells can be run in parallel
with a turndown flow that is the larger of (1) the flow
produced by the smallest pump or (2) 50 percent of
the design flow for the cell.
Each fan powered by a motor of 7.5 hp (5.6 kW) or larger shall have the capability to operate that fan at two-thirds of full speed or less, and shall have controls that automatically change the fan speed to control the leaving fluid temperature or condensing temperature/pressure of the heat rejection device.
Exception: Factory-installed heat rejection devices within HVAC equipment tested and rated in accordance with Tables 503.2.3(6) and 503.2.3(7).
Sections 503.4.5.1 through 503.4.5.3 shall apply to complex mechanical systems serving multiple zones. Supply air systems serving multiple zones shall be VAV systems which, during periods of occupancy, are designed controlled to comply with all of the following:
Reduce primary air supply to each zone to one of the following when the zone temperature is in a 5°F (3°C) zone temperature dead band after cooling is no longer required and before reheating, recooling or mixing takes place:
Twenty percent of the maximum supply air to each zone.
Three hundred cfm (142 L/s) or less where the maximum flow rate is less than 10 percent of the total fan system supply airflow rate.
The minimum ventilation requirements of Chapter 4 of the Mechanical Code unless increasing the volume to critical zones (zones with the highest ratio of outside air to total supply air) beyond the minimum ventilation requirements results in a decrease in overall outside air required by the HVAC system. An increase beyond minimum ventilation rates shall not be applied to more than 20 percent of the zones with reheat.
The volume of air that is reheated, recooled, or mixed in peak heating demand shall be less than 50 percent of the zone design peak supply rate.
Airflow between dead band and full heating or full cooling shall be modulated.
Exception: The following define when individual zones or when entire air distribution systems are exempted from the requirement for VAV control:
Zones where special pressurization relationships or cross-contamination requirements are such that VAV systems are impractical.
Zones or supply air systems where at least 75 percent of the energy for reheating or for providing warm air in mixing systems is provided from a site-recovered or site-solar energy source.
Zones where special humidity levels are required to satisfy process needs.
Zones with a peak supply air quantity of 300 cfm (142 L/s) or less and where the flow rate is less than 10 percent of the total fan system supply airflow rate.
Zones where the volume of air to be reheated, recooled or mixed is no greater than the volume of outside air required to meet the minimum ventilation requirements of Chapter 4 of the International Mechanical Code.
Zones or supply air systems with thermostatic and humidistatic controls capable of operating in sequence the supply of heating and cooling energy to the zone(s) and prevent reheating, recooling, mixing or simultaneous supply of air that has been previously cooled, either mechanically or through the use of economizer systems, and air that has been previously mechanically heated.
Systems that have one warm air duct and one cool air duct shall use terminal devices which
reduce the flow from one duct to a minimum before mixing of air from the other duct takes place.
HVAC systems serving multiple zones, including dedicated
outside air systems shall include controls that automatically
reset the supply-air temperature in response to
representative building loads, or to outdoor air temperature.
The controls shall be capable of resetting the supply
air temperature at least 35 percent of the difference
between the design supply-air temperature and the
design room air temperature. Controls that adjust the
reset based on zone humidity control requirements are
allowed. Zones which are expected to experience relatively
constant loads, such as electronic equipment
rooms or interior zones without reheat, shall be designed
for the fully reset supply temperature.
Exceptions:
Systems that prevent reheating, recooling or mixing
of heated and cooled supply air.
75 percent of the energy for reheating is from
site-recovered or site solar energy sources.
Where the total installed heat rejection capacity
of water-cooled chillers exceeds 6,000,000 Btu/h (1 758
600 W) and the combined design reheat, dual duct heating,
and service water heating load exceeds 1,000,000
Btu/h (293 100W), all the following shall apply:
Condenser heat recovery shall be installed for
heating or preheating of service hot water, heating
water for reheat, or dual-duct system heating.
Reheat coils and dual duct heating coils shall be
hydronic; except VAV zones with design airflow
less than 500 cfm (236 L/s) may have electric
reheat.
The required heat recovery system shall have the
capacity to provide the smaller of:
30 percent of the peak heat rejection load at
design conditions; or
The preheating required to raise the peak
service hot water draw to 85°F (29°C) plus
10 percent of the design reheat or dual-duct
heating load.
Exception: Facilities that provide 25 percent of their
combined design service water heating, reheat, and
Dual Duct heating from site solar or site recovered
energy, such as geothermal heat recovery or combined
heat and power.
Cooling systems shall not use hot gas bypass or other evaporator pressure control systems unless the system is designed with multiple steps of unloading or continuous capacity modulation. The capacity of the hot gas bypass shall be limited as indicated in Table 503.4.7.
Exception: Unitary packaged systems with cooling capacities not greater than 90,000 Btu/h (26 379 W).
Water-heating equipment and hot water storage tanks shall meet the requirements of Table 504.2. The efficiency shall be verified through data furnished by the manufacturer or through certification under an approved certification program.
TABLE 504.2 MINIMUM PERFORMANCE OF WATER-HEATING EQUIPMENT
Energy factor (EF) and thermal efficiency (Et) are minimum requirements. In the EF equation, V is the rated volume in gallons.
Standby loss (SL) is the maximum Btu/h based on a nominal 70°F temperature difference between stored water and ambient requirements. In the SL equation, Q is the nameplate input rate in Btu/h. In the SL equation for electric water heaters, V is the rated volume in gallons
and Vm is the measured volume gallons. In the SL equation for oil and gas water heaters and boilers, V is the rated volume in gallons.
Instantaneous water heaters with input rates below 200,000 Btu/h
shall comply with these requirements if the water heater is designed to heat water to temperatures 180°F or higher.
Electric water heaters with an input rating of 12kW or less that are designed to heat water to temperatures of 180°F or greater shall comply with the requirements for electric water heaters that have an input rating greater than 12kW.
Service water-heating equipment shall be provided with controls to allow a setpoint of
120°F (49°C) for equipment serving dwelling units and 90°F (32°C) for equipment serving other occupancies. The outlet temperature of lavatories in public facility rest rooms shall be limited to 120°F (49°C).
Water-heating equipment not supplied with integral heat traps and serving noncirculating systems shall be provided with heat traps on the supply and discharge piping associated with the equipment.
For automatic-circulating hot water
and externally heated (such as heat trace or impedance heating) systems, piping shall be insulated with 1 inch (25 mm) of insulation having a conductivity not exceeding 0.27 Btu per inch/h × ft2 × °F (1.53 W per 25 mm/m2 × K). The first 8 feet (2438 mm) of piping in noncirculating systems served by equipment without integral heat traps shall be insulated with 0.5 inch (12.7 mm) of material having a conductivity not exceeding 0.27 Btu per inch/h × ft2 × °F (1.53 W per 25 mm/m2 × K).
Systems designed to maintain
usage temperatures in hot water pipes, such as hot water
recirculating systems or heat trace, shall be turned off automatically
when the hot water system is not operational and shall have
demand sensing controls (flow switch in cold water make-up
pipe, return water aqua stat temperature sensor) that turn off the
system when there is no demandwhen the system is operational.
A check valve or similar device shall be located between the
circulator pump and the water heating equipment to prevent
water from flowing backwards though the recirculation loop.
Gravity or thermosyphon circulation loops are prohibited.
Exceptions:
Where public health standards require 24 hours per
day operation of pumps for uses such as swimming
pools, spas and hospitals.
Service water heating systems used to provide multiple
functions (e.g., space heating andDHW)as part of
an integrated system.
Where coupled with water heating capacity less than
100,000 Btu/h (29 kW).
All heaters shall be equipped with a readily accessible on-off switch to allow shutting off the heater without adjusting the thermostat setting. heaters fired by natural gas or LPG shall not have continuously burning pilot lights.
Time switches that can automatically turn off and on heaters and pumps according to a preset schedule shall be installed on heaters and pumps.
Exceptions:
Where public health standards require 24-hour pump operation.
Swimming pools and spas are regulated by the Oregon Health Authority perOAR 333-062. In the event of conflict with this code, OAR 333-062 shall prevail.
Where pumps are required to operate solar-and waste-heat-recovery pool heating systems.
Heated
pools, spas and hottubs shall be equipped with a vapor retardant cover on or at the water surface.
Pools, spas and hottubs heated to more than 90°F (32°C) shall have a
cover with a minimum insulation value of R-12.
Exception:
Pools, spas and hottubs deriving over 60 percent of the energy for heating from site-recovered energy or solar energy source.
Heated indoor swimming pools,
spas, or hot tubs with water surface area greater than 200
square feet (19 m2) shall provide heat recovery utilizing
either:
Compressorized dehumidification system with integral
reheat and:
Condensor heat recover for water heating of
pool and/or service hot water, or
Exhaust air heat recovery that recovers 50 percent
of the total energy from the pool enclosure
exhaust air stream at design heating conditions.
Air-to-air exchange system with variable outdoor
air/exhaust and variable heat exchanger bypass, set to
maintain maximum space relative humidity of 60 percent.
At 50°F dry bulb and 80-percent relative humidity
outdoor conditions, the heat exchanger shall
increase the total energy of the incoming outdoor air
by 60 percent or shall increase the sensible energy of
the outdoor air by 70 percent.
Exception: Pools, spas, or hot tubs that include system(s) that provide equivalent recovered energy on an
annual basis through one of the following methods:
Heated by renewable energy,
Waste heat recovery, or
A combination of these system(s) sources capable
of providing at least 70 percent of the heating
energy required over an operating season.
This section covers lighting system controls, the connection of ballasts, the maximum lighting power for interior applications and minimum acceptable lighting equipment for exterior applications.
Exception:
Lighting within dwelling units where 50 percent or more of the permanently installed interior light fixtures are fitted with high-efficacy lamps.
At least one local shutoff lighting
control shall be provided for every 2,000 square feet
(185.8 m2) of lit floor area and each area enclosed by walls or floor-to-ceiling partitions. The required controls shall be located within the area served by the controls or be a remote switch that identifies the lights served and indicates their status.
Exceptions:
Lighting systems serving areas designated as security or emergency areas that must be continuously lighted.
Lighting in public areas such as concourses, stairways or corridors that are elements of the means of egress with switches that are accessible only to authorized personnel.
Lighting for warehouses, parking garages or
spaces using less than 0.5 watts per square foot
(5.4 W/m2).
Lighting for contiguous, single-tenant retail
spaces.
Egress illumination shall be
controlled by a combination of listed emergency relay
and occupancy sensors to shut off during periods that the
building space served by the means of egress is unoccupied.
Exception: Building exits as defined in Section 1002
of the Building Code.
Each area that is required to have a manual control shall also allow the occupant to reduce the connected lighting load in a reasonably uniform illumination pattern by at least 50 percent. Lighting reduction shall be achieved by one of the following or other approved method:
Controlling all lamps or luminaires(dimming or multilevel switching);
Dual switching of alternate rows of luminaires, alternate luminaires or alternate lamps;
Switching the middle lamp luminaires independently of the outer lamps; or
Buildings larger than
2,000 square feet (186 m2) shall be equipped with an automatic control device to shut off lighting in those areas. This automatic control device shall function on either:
A scheduled basis, using time-of-day, with an independent program schedule that controls the interior lighting in areas that do not exceed
10,000 square feet (929 m2) and are not more than one floor; or
An occupant sensor that shall turn lighting off within 30 minutes of an occupant leaving a space; or
A signal from another control or alarm system that indicates the area is unoccupied.
Occupancy sensors in rooms that include daylight
zones are required to have Manual ON activation,
An occupant sensor control device shall be installed
that automatically turns lighting off within 30 minutes of
all occupants leaving a space, except spaces with
multi-scene control, in:
Classrooms and lecture halls.
Conference, meeting and training rooms.
Employee lunch and break rooms.
Rooms used for document copying and printing.
Office spaces up to 300 square feet (29 m2).
Restrooms.
Dressing, fitting and locker rooms.
An occupant sensor control device that automatically
turns lighting off within 30 minutes of all occupants leaving
a space or a locally activated switch that automatically
turns lighting off within 30 minutes of being
activated shall be installed in all storage and supply
rooms up to 1000 square feet (93 m2).
Exception: The following shall not require an automatic control device:
Where an automatic time switch control device is installed to comply with Section 505.2.2.2, Item 1, it shall incorporate an override switching device that:
Is located so that a person using the device can see the lights or the area controlled by that switch, or so that the area being lit is annunciated.
Is manually operated.
Allows the lighting to remain on for no more than 2 hours when an override is initiated.
Controls an area not exceeding
2,000
square feet
(185.8
m2).
Exceptions:
In malls and arcades, auditoriums, single-tenant retail spaces, industrial facilities and arenas, where captive-key override is utilized, override time shall be permitted to exceed 2 hours.
In malls and arcades, auditoriums, single-tenant retail spaces, industrial facilities and arenas, the area controlled shall not exceed 20,000 square feet (1860 m2).
If an automatic time switch control device is installed in accordance with Section 505.2.2.2, Item 1, it shall incorporate an automatic holiday scheduling feature that turns off all loads for at least 24 hours, then resumes the normally scheduled operation.
Exceptions:
Retail stores and associated malls, restaurants,
grocery stores, places of religious worship,
theaters and exterior lighting zones.
Single zone electronic time control devices
and self-contained wall box preset lighting
controls.
Alldaylight zones, as defined by this code, shall be provided with individual controls that control the lights independent of general area lighting
in the nondaylight zone.In all individualdaylight zoneslarger
than
350 square feet (33 m2), automatic
daylight controls shall be provided.
Automatic daylight sensing controls shall reduce the
light output of the controlled luminaires within the
daylighted area by at least 50 percent, and provide an
automatic OFF control, while maintaining a uniform
level of illumination.
Contiguous daylight zones adjacent to vertical fenestration
are allowed to be controlled by a single controlling
device provided that they do not include zones
facing more than two adjacent cardinal orientations (i.e., north, east, south, west). Daylight zones under skylights
shall be controlled separately from daylight zones adjacent
to vertical fenestration.
Exceptions:
Retail spaces adjacent to vertical glazing (retail
spaces under overhead glazing are not exempt).
Sleeping units in hotels, motels, boarding houses or similar buildings shall have at least one master switch at the main entry door that controls all permanently wired luminaires and switched receptacles, except those in the bathroom(s).
Bathrooms shall have a
control device installed to automatically turn off the bathroom
lighting, except for night lighting not exceeding 5
watts, within 60 minutes of the occupant leaving the space.
A building complies with this section if its total connected lighting power calculated under Section 505.5.1 is no greater than the interior lighting power calculated under Section 505.5.2or 505.5.2.1.
The total connected interior lighting power (watts) shall be the sum of the watts of all interior lighting equipment as determined in accordance with Sections 505.5.1.1 through 505.5.1.4.
Exceptions:
The connected power associated with the following lighting equipment is not included in calculating total connected lighting power.
Sleeping unit lighting in hotels, motels, boarding houses or similar buildings.
Emergency lighting automatically off during normal building operation.
Lighting in spaces specifically designed for use by occupants with special lighting needs including the visually impaired visual impairment and other medical and age-related issues.
Lighting in interior spaces that have been specifically designated as a registered interior historic landmark.
Casino gaming areas.
Lighting equipment used for the following shall be exempt provided that it is in addition to general lighting and is controlled by an independent control device:
Task lighting for medical and dental purposes.
Display lighting for exhibits in galleries, museums and monuments.
Lighting for theatrical purposes, including performance, stage, film production and video production.
Lighting for photographic processes.
Lighting integral to equipment or instrumentation and is installed by the manufacturer.
Task lighting for plant growth or maintenance.
Advertising signage or directional signage.
In restaurant buildings and areas, lighting for food warming or integral to food preparation equipment.
Lighting equipment that is for sale.
Lighting demonstration equipment in lighting education facilities.
Lighting integral to both open and glass-enclosed refrigerator and freezer cases.
Lighting in retail display windows, provided the display area is enclosed by ceiling-height partitions.
Furniture mounted supplemental task lighting that is controlled by automatic shutoff.
The wattage of all other lighting equipment shall be the wattage of the lighting equipment verified through data furnished by the manufacturer or other approved sources.
The total interior lighting power (watts) is the sum of all interior lighting powers for all areas in the building covered in this permit. The interior lighting power is the floor area for each building area type listed in Table 505.5.2(a) times the value from Table 505.5.2(a) for that area. For the purposes of this method, an "area" shall be defined as all contiguous spaces that accommodate or are associated with a single building area type as listed in Table 505.5.2(a). When this method is used to calculate the total interior lighting power for an entire building, each building area type shall be treated as a separate area.
For SI: 1 foot = 304.8 mm, 1 square foot = 0.929 m2, W/m2=W/ft2 × 10.764.
The watts per square foot may be increased by 2 percent per foot of ceiling height above 20 feet unless specified differently by another footnote.
The watts per square foot of room may be increased by 2 percent per foot of ceiling height above 9 feet.
Hotel banquet room, conference rooms, or exhibit hall watt per square foot of room may be increased by 2 percent per foot of ceiling height above 12 feet.
Spaces used specifically for manufacturing are exempt.
The total interior
connected lighting power shall not exceed the maximum
power allowance calculated by multiplying the lighting
power density from Table 505.5.2(b) for each space by
the floor area of that space. Parking garages and exterior
canopies shall be treated separately from the building for
the purposes of calculating interior connected lighting
power.
For lighting equipment installed in retail sales
area that is specifically designed and directed to highlight
merchandise, one of the following may apply:
0.6 watts per square foot of sales floor area not
listed in 2 or 3 below; or
1.4 watts per square foot of furniture, clothing,
cosmetics or artwork floor area; or
2.5 watts per square foot of jewelry, crystal; or
china floor area.
The specified floor area for 1, 2, and 3 above, and
the adjoining circulation paths shall be identified and
specified on building plans. Calculate the additional
power allowance by multiplying the above LPDs by
the sales floor area for each department excluding
major circulation paths. The total additional lighting
power allowance is the sum of allowances sales categories,
1, 2, or 3. This additional lighting power shall
only be used for retail display lighting in the applicable
space, and shall not be used to increase lighting
power allowance with other spaces or general lighting
system within the space and shall be controlled separately
from the space general lighting system.
When the power for exterior lighting is supplied through the energy service to the building, all exterior lighting, other than low-voltage landscape lighting, shall comply with Sections 505.6.1 and 505.6.2.
Exception:
Where approved because of historical, safety, signage or emergency considerations.
No incandescent
or mercury vapor lighting sources shall be used for
exterior building lighting.
Exceptions:
Incandescent lighting used in or around swimming
pools, water features, or other locations subject to
the requirements of Article 680 of the Electrical
Code.
Incandescent luminaires controlled by motion sensors
with total power less than 150 watts.
The total exterior lighting power allowance for all exterior building applications is the sum of the base site allowance plus the individual allowances for areas that are to be illuminated and are permitted in Table 505.6.2(2) for the applicable lighting zone. Tradeoffs are allowed only among exterior lighting applications listed in Table 505.6.2(2), Tradable Surfaces section. The lighting zone for the building exterior is determined from Table 505.6.2(1) unless otherwise specified by the local jurisdiction. Exterior lighting for all applications (except those included in the exceptions to Section 505.6.2) shall comply with the requirements of Section 505.6.1.
Exceptions: Lighting used for the following exterior applications is exempt when equipped with a control device independent of the control of the nonexempt lighting:
Specialized signal, directional and marker lighting associated with transportation;
Advertising signage or directional signage;
Integral to equipment or instrumentation and is installed by its manufacturer;
Theatrical purposes, including performance, stage, film production and video production;
Athletic playing areas;
Temporary lighting;
Industrial production, material handling, transportation sites and associated storage areas;
Theme elements in theme/amusement parks; and
Used to highlight features of public monuments and registered historic landmark structures or buildings.
Developed areas of national parks, state parks, forest land, and rural areas
2
Areas predominantly consisting of residential zoning, neighborhood business districts, light industrial with limited nighttime use and residential mixed use areas
3
All other areas not classified as lighting zone 1, 2 or 4.
4
High-activity commercial districts in major metropolitan areas as designated by the local land use planning authority
TABLE 505.6.2(2) INDIVIDUAL LIGHTING POWER ALLOWANCES FOR BUILDING EXTERIORS
Base Site Allowance (Base allowance may be used in tradable or nontradable surfaces.)
500 W
600 W
750 W
1300 W
Tradable Surfaces (Lighting power densities for uncovered parking areas, building grounds, building entrances and exits, canopies and overhangs and outdoor sales areas may be traded.)
Uncovered Parking Areas
Parking areas and drives
0.04 W/ft2
0.06 W/ft2
0.10 W/ft2
0.13 W/ft2
Building Grounds
Walkways less than 10 feet wide
0.7 W/linear foot
0.7 W/linear foot
0.8 W/linear foot
1.0 W/linear foot
Walkways 10 feet wide or greater, plaza areas special feature areas
0.14 W/ft2
0.14 W/ft2
0.16 W/ft2
0.2 W/ft2
Stairways
0.75 W/ft2
1.0 W/ft2
1.0 W/ft2
1.0 W/ft2
Pedestrian tunnels
0.15 W/ft2
0.15 W/ft2
0.2 W/ft2
0.3 W/ft2
Building Entrances and Exits
Main entries
20 W/linear foot of door width
20 W/linear foot of door width
30 W/linear foot of door width
30 W/linear foot of door width
Other doors
20 W/linear foot of door width
20 W/linear foot of door width
20 W/linear foot of door width
20 W/linear foot of door width
Entry canopies
0.25 W/ft2
0.25 W/ft2
0.4 W/ft2
0.4 W/ft2
Sales Canopies
Free-standing and attached
0.6 W/ft2
0.6 W/ft2
0.8 W/ft2
1.0 W/ft2
Outdoor Sales
Open areas (including vehicle sales lots) and food service
0.25 W/ft2
0.25 W/ft2
0.5 W/ft2
0.7 W/ft2
Street frontage for vehicle sales lots in addition to "open area" allowance
No allowance
10 W/linear foot
10 W/linear foot
30 W/linear foot
Nontradable Surfaces (Lighting power density calculations for the following applications can be used only for the specific application and cannot be traded between surfaces or with other exterior lighting. The following allowances are in addition to any allowance otherwise permitted in the "Tradable Surfaces" section of this table.)
Building facades and roof pathsa
No allowance
0.1 W/ft2 for each illuminated wall or surface or 2.5 W/linear foot for each illuminated wall or surface length
0.15 W/ft2 for each illuminated wall or surface or 3.75 W/linear foot for each illuminated wall or surface length
0.2 W/ft2 for each illuminated wall or surface or 5.0 W/linear foot for each illuminated wall or surface length
Automated teller machines and night depositories
270 W per location plus 90 W per additional ATM per location
270 W per location plus 90 W per additional ATM per location
270 W per location plus 90 W per additional ATM per location
270 W per location plus 90 W per additional ATM per location
Entrances and gatehouse inspection stations at guarded facilities
0.75 W/ft2 of covered and uncovered area
0.75 W/ft2 of covered and uncovered area
0.75 W/ft2 of covered and uncovered area
0.75 W/ft2 of covered and uncovered area
Loading areas for law enforcement, fire, ambulance and other emergency service vehicles
0.5 W/ft2 of covered and uncovered area
0.5 W/ft2 of covered and uncovered area
0.5 W/ft2 of covered and uncovered area
0.5 W/ft2 of covered and uncovered area
Drive-up windows/doors
400 W per drive-through
400 W per drive-through
400 W per drive-through
400 W per drive-through
Parking near 24-hour retail entrances
800 W per main entry
800 W per main entry
800 W per main entry
800 W per main entry
For SI: 1 foot = 304.8 mm, 1 watt per square foot = W/0.0929 m2.
Roof lighting: larger of either total roof area or total access/maintenance walkway path length.
Lighting not designated
for dusk-to-dawn operation shall be controlled by
either a combination of a photosensor and a time switch, or
an astronomical time switch. Lighting designated for
dusk-to-dawn operation shall be controlled by an astronomical
time switch or photosensor. All time switches shall
retain programming and the time setting during loss of
power for a period of at least 10 hours. Lighting designated
to operate more than 2000 hours per year for uncovered
parking areas shall be equipped with motion sensors that
will reduce the luminaire power by 33 percent or turn off
one-third the luminaires when no activity is detected.
In buildings having individual dwelling units, provisions shall be made to determine the electrical energy consumed by each tenant by separately metering individual dwelling units.
Applicants shall demonstrate that the whole building annual energy consumption will not exceed that used by a similar building using similar forms of energy design in accordance with the prescriptive requirements of this code. Compliance under this section allows tradeoffs between building components using an 8,760 - hour annual building simulation. Information and criteria for demonstrating compliance using the WBA is available at http://www.bcd.oregon.gov.
All distribution transformers
shall meet the minimum efficiency levels specified in Tables
507.1 and 507.2. All other terms and provisions of National
Electrical Manufacturers Association (NEMA) Standard
TP 1-1996, Guide for Determining Energy Efficiency for
Distribution Transformers, shall apply to distribution transformers.
These requirements shall apply to transformers
within the scope of TP 1-1996.
Exceptions:
Liquid-filled transformers below 10 kVA.
Dry-type transformers below 15 kVA.
Drive transformers designed only to operate
electronic variable speed AC and DC drives.
Rectifier transformers designed only to power
rectifier circuits that have nameplate ratings for
fundamental frequency and RMS.
High harmonic transformers with a K-rating of
K-4 or greater that are designed to supply loads
with higher than normal harmonic current levels.
A licensed engineer shall submit verification of
need for harmonic current control.
Autotransformers in which the primary and secondary
windings are not electrically isolated, and
in which secondary voltage is derived from at least a portion of the primary winding as specified
by a licensed engineer.
Nondistribution transformers, such as those
designed as an integral part of an uninterruptible
power system (UPS).
Transformers with special impedance outside the
following ranges: 1.5 percent to 7.0 percent for
15 kVA - 150 kVA units, 3.0 percent to 8.0 percent
for 167 kVA - 500 kVA units, and 5.0 percent
to 8.0 percent for 667 kVA - 2500 kVA units.
Voltage regulating transformers with load tap
changing gear.
Sealed transformers that are designed to remain
hermetically sealed and nonventilated transformers
designed to prevent airflow through the
transformer.
Replacement of an existing transformer where a
qualified TP-1 transformer will not fit in the
space provided.
Transformers feeding circuits dedicated to
machine tools and/or welders.
Transformers with tap ranges greater than 15
percent or with frequencies other than 50 to 60
Hz.
Grounding transformers that only provide a system
ground reference point, or testing transformers
that are part of, or supply power to electrical
test equipment.
TABLE 507.1
NEMA CLASS 1 EFFICIENCY LEVELS FOR LIQUID-FILLED DISTRIBUTION TRANSFORMERS1
SINGLE PHASE
THREE PHASE
kVa
Efficiency
kVa
Efficiency
10
98.3%
15
98.0%
15
98.5%
30
98.3%
25
98.7%
45
98.5%
37.5
98.8%
75
98.7%
50
98.9%
112.5
98.8%
75
99.0%
150
98.9%
100
99.0%
225
99.0%
167
99.1%
300
99.0%
250
99.2%
500
99.1%
333
99.2%
750
99.2%
500
99.3%
1,000
99.2%
667
99.4%
1,500
99.3%
833
99.4%
2,000
99.4%
2,500
99.4%
Efficiency is calculated per conditions stated in NEMA Standard TP 1-1996.
TABLE 507.2
NEMA CLASS 1 EFFICIENCY LEVELS FOR DRY-TYPE DISTRIBUTION TRANSFORMERS1
SINGLE PHASE EFFICIENCY
THREE PHASE EFFICIENCY
kVa
Low Voltage
Medium Voltage
kVa
Low Voltage
Medium Voltage
15
97.7%
97.6%
15
97.0%
96.8%
25
98.0%
97.9%
30
97.5%
97.3%
37.5
98.2%
98.1%
45
97.7%
97.6%
50
98.3%
98.2%
75
98.0%
97.9%
75
98.5%
98.4%
112.5
98.2%
98.1%
100
98.6%
98.5%
150
98.3%
98.2%
167
98.7%
98.7%
225
98.5%
98.4%
250
98.8%
98.8%
300
98.6%
98.5%
333
98.9%
98.9%
500
98.7%
98.7%
500
—
99.0%
750
98.8%
98.8%
667
—
99.0%
1,000
98.9%
98.9%
833
—
99.1%
1,500
—
99.0%
2,000
—
99.0%
2,500
—
99.1%
Efficiency is calculated per conditions stated in NEMA Standard TP 1-1996.
All distribution transformers shall be
tested in accordance with National Electrical Manufacturers
Association (NEMA) TP 2-1998, Standard Test Method for
measuring the Energy Consumption of Distribution Transformers.
All distribution transformers shall be
labeled in accordance with National Electrical Manufacturers
Association (NEMA) TP 3-2000, Standard for the
Labeling of Distribution Transformer Efficiency.