About the International Glazing Database (IGDB)The IGDB is a collection of optical data for glazing products. Spectral transmittance and reflectance measured in a spectrophotometer and contributed to the IGDB by the manufacturer of the glazing product subject to a careful review. If your goal is to submit data, you can skip to the instructions, but if you are new to the process, first you may wish to skim the answers to FAQs immediately following. What are the relationships between LBNL, the NFRC and the IGDB? LBNL maintains and publishes the IGDB. NFRC is by far the single most important user of the IGDB. The NFRC window rating system is powered by the LBNL Window5 program (see next section), which in turn relies on the IGDB for input data. NFRC charges a fee to the data supplier for any data that is used in the rating system. Some of this NFRC revenue is used to support LBNL for the operation of collecting the data. Department of Energy (DOE) provides support for the optical laboratory, participation in standards activities and related research. There is no fee for data not used for NFRC rating, at present, but all data goes through the same review process! You may contact either LBNL or NFRC to begin the process. Is the IGDB a part of the LBNL Window5 or Optics5 program?A very close relationship exists, and the IGDB is part of the download package with Window5 or Window6.. Most of the experimental input data required by Window5/6 to calculate the energy performance indices (e.g., U-factor and g-factor) of a window comes from the IGDB. Other programs developed at LBNL and elsewhere can read data from the IGDB. A common occurrence is a request for a password to open the IGDB file directly in MS Access. Such a request is seldom granted because the intention is to open the IGDB directly with Window5/6 or other approved program, so as to avoid spreading modified versions of the tested database. Especially in the interests of international harmonization, however, permission might be granted to a reputable agency. The most basic purpose of Window5/6 is to calculate the properties of combination's of simple glazing materials (e.g., double and triple glazing units), whose properties are drawn from the IGDB. What types of materials are passed through the review process? As of the date on this page, only specular glazing materials, however complex in structure, are passed through the review process. This could be monolithic glass, plastic, laminates, applied films on glass, or thin-film coated glass. Diffusing or light redirecting glazing or shading devices are not allowed at present. This situation is rapidly approaching a major change with the release of Window6 and the CGDB. The major impediment is the lack of a reliable standard test procedure diffusing components and for complex shading systems. One type of "attachment" product present in the IGDB is the applied film. Although technically a retrofit product like other types of shading systems, it has the distinction of also being a specular material. Thus, it can easily be incorporated into the technical part of the rating system although the procedure defined by NFRC 304 is different than for an originally purchased window unit. There is a measurement issue relating to the interference fringes common in applied films that is different from other types of specular glazing. What software is used with the IGDB?It is even possible to design new
glazing materials such as laminates and applied films by combining
sub-components such as glass, interlayer and coating, derived from
materials in the IGDB, using the Optics5
software or similar programs. This process is not without potential for
mishap as described in the separate blog on the danger of
calculated data How do I submit data to to the IGDB?If you are ready to submit data to the IGDB, follow these instructions. Please note that these instructions are unofficial and not approved by either LBNL or NFRC. Official instructions can be found on both the LBNL IGDB webpage and the NFRC IGDB webpage. Why do I add a third set of instructions, when two sets of instructions are already one set too many? Simply put, because it is necessary to sort out the redundancy and confusion of the other two instruction sets. It is easier for me to rewrite the procedures from scratch, linking to the best parts of the other sites and flagging those parts which cannot be supported. After review by LBNL and NFRC, I expect that these instructions will be ported to their official websites. You will be successful in submitting data if you follow these instructions. Page revised on 8 October 2009 by Mike Rubin |