Commonly Used Abbreviations
Additional definitions and terminology may be found in NFRC 600: Glossary and Terminology.
NFRC – National Fenestration Rating Council – a nonprofit research/educational organization (501(c) 3) that develops and administer energy-related rating and certification programs that serve the public by providing fair, accurate, and credible information on fenestration performance.
ACE – Approved Calculation Entity: An individual, who has attended an NFRC Calculation Training Workshop, completed and passed all necessary examinations, and has obtained a Certificate of Approval which qualifies him or her to carry out performance calculations of fenestration products for certification using the Component Modeling Approach.
AM – Air Mass: The ratio of the mass of atmosphere along the actual observer-to-sun line to the mass that would exist if the observer was at sea level, at standard barometric pressure, and if the sun was directly overhead (at the zenith).AMC – Attachment Manufacturer’s Certificate.
APC - Accreditation Policy Committee: A standing committee whose members are appointed by the NFRC Board of Directors to manage the NFRC Laboratory Accreditation Program (LAP). See the NFRC 710: Operating Policies Manual for further details.
APD – Applied Films Product Directory
ASL/ATL – Accredited Simulation/Testing Laboratory: Computer simulation or testing laboratory that has met NFRC Laboratory Accreditation Program (LAP) requirements, has entered into a NFRC laboratory License Agreement, and received a NFRC Certificate of Accreditation, none of which has been revoked.
CAMP – Compliance and Monitoring Program: NFRC administers this program that monitors program activity and assists and educates architects, builders, code officials and other regulatory agencies. The governing document for this program is the NFRC 707.
CAP – Certification Agency Program: NFRC administers this program which includes a set of rules and procedures by which an independent certification and inspection agency becomes licensed and operates. The governing document for this program is the NFRC 702.
CEAP – Calculation Entity Approval Program: NFRC administers this program that contains the rules and requirements for becoming an Approved Calculation Entity (ACE) and ACE Organization in the CMA Program. The governing document for this program is the NFRC 708.CMA – Component Modeling Approach: A new rating methodology being developed by NFRC to address fenestration in commercial buildings.
CMA PCP – Component Modeling Approach Product Certification Program: NFRC administers this program which contains the rules and requirements for component manufacturers/participants seeking spacer and frame component approval and Specifying Authorities seeking product certification by requesting a CMA Label Certificate. The governing document for this program is the NFRC 705.
CMAST CPD –Component Modeling Approach Software Tool Certified Products Directory: A freely accessible, web-based directory administered by NFRC that provides energy rating information for non-residential fenestration products as well as NFRC-approved components, and a listing of all CMA Label Certificates.
CPC – Certification Policy Committee: A standing committee whose members are appointed by the NFRC Board of Directors to manage the NFRC Certification Agency Program (CAP) and to provide interpretations for the NFRC Product Certification Program (PCP). See the NFRC 710: Operating Policies Manual for further details.
CPD – Certified Products Directory: A directory of fenestration products in electronic form, listing fenestration products and their performance ratings, for which product certification authorization has been granted by a licensed IA (inspection agency), and can be searched by the public.
CPD Number – Certified Products Directory Number: A unique identification number assigned by NFRC via the CPD to an authorized product.
CTS – Calibration Transfer Standard: An insulation board that is faced with glazing, instrumented with temperature sensors between the glazing and the insulation board core, which is used to calibrate the surface heat transfer coefficients and the surround panel.
FMC – Fenestration Manufacturer’s Certificate: An FMC may be used by a manufacturer under specific conditions in the event that a properly applied NFRC temporary label has been removed, or at the manufacturer’s discretion upon request from a responsible party (i.e., building code official, builder, homeowner, etc.)
Fenestration – Products that fill openings in a building envelope, such as windows, doors, skylights, curtain walls, etc., designed to permit or limit the passage of air, light, vehicles, or people.
Fenestration Attachment – A device (such as, but not limited to, shades, films, or blinds) designed to be physically attached to, incorporated with or covering a fenestration product.
Film -- Fenestration attachment products which consist of a flexible adhesive-backed polymer film which may be applied to the interior or exterior surface of an existing glazing system. See Fenestration Attachment.
HTDD – Hybrid Tubular Daylighting Device: A tubular daylighting device (TDD) whose light transmitting tube consists of more than one material and/or has more than one geometry throughout its length. Typically used with suspended ceilings or to illuminate spaces without ceilings.
IA - Independent Certification and Inspection Agency:An organization or person authorized by license to conduct specified services for the Certification Program.
IAC – Inter-Agency Comparison: Organization, performance, and evaluation of certification authorization processes by two or more certification agencies in accordance with predetermined results and/or submissions.
IG/IGU – Insulating Glass Unit: A preassembled unit comprising lites of glass, which are sealed at the edges and separated by dehydrated space(s). The unit is normally used for windows, window walls, picture windows, sliding doors, patio doors, or other types of fenestration. (SIG – Sealed Insulating Glass Unit)
ILC – Interlaboratory Comparison: Organization, performance, and evaluation of the same test sample or simulation by two or more laboratories in accordance with predetermined conditions.
IRC – Individual-in-responsible-charge: The individual(s) responsible for assuring that the quality of services offered and provided by an Licensed Certification Program are in full compliance with the NFRC 700, NFRC 702, and NFRC 705. An IRC shall participate in any workshops associated with the NFRC 702.
IRV -- Identical Rating Values
IVP – The Independent Verification Program: A requirement because of NFRC’s status as an approved Certification Body (CB) for the ENERGY STAR ® Windows Program. This is a program that will verify the performance ratings of ENERGY STAR-qualified fenestration products sold in the market that agrees with the performance ratings listed in the NFRC Certified Products Directory. This program will use procedures that complement the inspection and validation testing requirements of the NFRC 700. Full implementation is anticipated to begin January 2013 upon the approval of the Board.
KD – Knocked Down Product: A fenestration product supplied by a licensed manufacturer/responsible party in an unassembled or partially assembled state, which requires further assembly at the jobsite.
LAP – Laboratory Accreditation Program: NFRC administers this program which contains the rules and requirements for licensed, accrediting thermal test and computer simulation laboratories. The governing document for this program is the NFRC 701.
OAVA – Outdoor Air Ventilator Assembly: An apparatus independent from but installed into a fenestration product for controlling the transfer of air through the product.
OWL – Outdoor Wetted Length: Measured from the interface between frame and glazing to the first adiabatic boundary on the outdoor side.
PCP – Product Certification Program: NFRC administers this program which contains the rules and requirements for licensed manufacturers/participants to label windows (and responsible parties to produce Label Certificates). The governing document for this program is the NFRC 700.
RH – Relative Humidity: The ratio of the amount of water vapor in the air compared to the maximum amount of water vapor that the air could hold at a particular temperature and pressure.
SIRC – Simulator-In-Responsible-Charge: The individual(s) responsible for assuring that the quality of services offered and provided by an Accredited Simulation Laboratory are in full compliance with the LAP. An SIRC shall have successfully completed an NFRC Simulation Accreditation Workshop, passed an NFRC Simulation Accreditation Examination, attended an NFRC Annual Accreditation Workshop, and participate in any ILC evaluations in accordance with the LAP.
Site-Built Program – A rating program developed in 1999 by NFRC to rate non-residential fenestration products.
TB - Thermally Broken Members: System members with a minimum of 5.30 mm (0.210 in) separation provided by a thermal break.
TI - Thermally Improved Members: System members with a separation ≥ 1.60 mm (0.062 in) provided by either a thermal break or open air space that may be interrupted by short thermal bridges between the interior and exterior surfaces.
TDD - Tubular Daylighting Device: A non-operable device primarily designed to transmit daylight from a roof surface to an interior ceiling surface via a tubular conduit. The device consists of an exterior glazed weathering surface, a light transmitting tube with a reflective inside surface and an interior sealing device, such as a translucent ceiling panel. See also "Hybrid Tubular Daylighting Device.”
NFRC Energy Performance Ratings
AL- Air Leakage: The volume of air flowing per unit time per unit area through a fenestration system due to air pressure or temperature difference between the outdoor and indoor environment. (NFRC 400).
Condensation Resistance – A relative indicator of a fenestration product's ability to resist the formation of condensation at a specific set of environmental conditions. The higher the Condensation Resistance value the greater the resistance to the formation of condensation. (NFRC 500).
SHGC – Solar Heat Gain Coefficient: A rating that expresses the percentage of incident solar heat transmitted through a fenestration product; the lower the SHGC, the less solar heat gain (NFRC 200 and NFRC 201).
U-factor– Thermal Transmittance: A rating that expresses the rate of heat flow through the fenestration product. The lower the U-factor, the less heat is allowed to transfer through the fenestration product (NFRC 100 and NFRC 102).VT– Visible Transmittance: A rating that expresses the percentage of visible light transmitted through a fenestration product (NFRC 200).