Rating System

LEED BD+C: New Construction, LEED BD+C: Schools, LEED ID+C: Commercial Interiors

Rating System Version

v3 - LEED 2009, v2 - Schools 2007, v2 - LEED 2.2, v2 - LEED 2.0

Inquiry

Overview: This CIR applies to Option 2- Air Quality Testing. With regards to the process to demonstrate that the maximum TVOC concentrations are below 500 micrograms/cubic meter, this CIR is requesting the acceptance of an alternate unit of measure based on a volumetric reading from an instantaneous, direct reading photoionization detector instrument (PID) using a 10.6 eVolt lamp. This reading would be recorded in a ppb (parts per billion) measurement and then converted to the designated unit of measure called out in the requirements (micrograms/cubic meter) using a conversion factor. This direct reading approach for TVOC will offer a more economical solution for IAQ testing by a factor of approximately two for our ~480,000 SF project. Methodology A conversion factor has been developed (by EH&E in Newton, MA) and is based on a TVOC "fingerprint" of 33 individual volatile organic compounds grouped by chemical category, resulting from a technical evaluation of the Building Assessment Survey Evaluation (BASE) data, the EPA TO-15 list of VOC\'s, and other relevant technical data. The EH&E team examined three lists of indoor VOC\'s to develop the TVOC "fingerprint." These lists originated the following sources: BASE dataset for commercial buildings, PID-readable chemical compounds, and an EPA approved list of indoor VOC\'s. Seven individual VOC\'s from the BASE data the had the highest reported concentrations and could be measured by a PID formed an initial, preliminary fingerprint. These individual VOC\'s were chemically regrouped (i.e. alcohols, halogenated hydrocarbon, aliphatics, etc.) and the relative group proportions in the fingerprint were compared with the BASE dataset. Based on the EPA guidance and a review of indoor VOC literature, additional VOC\'s not measured in the BASE dataset were considered for inclusion. By mapping additional pollutants from the EPA TO-15 list of VOC\'s, EH&E modified the fingerprint to represent new or existing buildings. The expanded list of compounds included all BASE compounds that were both on the EPA TO-15 list and measurable by the PID. This "fingerprint" is based on the following list of chemicals, sorted by their group, their average group molecular weight (AGMV), the % in BASE data, and specific compounds in fingerprint: Format given in following order: Group/AGMW/% in BASE/Compounds in Fingerprint Aldehydes/44.06/12%/Acetaldehyde Alkanes & alkenes/113.6/8%/n-undecane; n-decane; Nonane; Octane; n-hexane; 1,3 butadiene Aromatics/110.5/14%/d-limonene; a-pinene; Naphthalene; o-xylene; m- & p-xylenes; Ethylbenzene; Styrene; Toluene; Benzene Halogenated Hydrocarbons/130/15%/1,2 -dbromoethane; 1,2, 4-trichlorobenzene; 1, 2, -dichlorobenzene; Trichlorobenzene; 1,3,5 -trimethylbenzene; Chlorobenzene; 1,1 -dichloroethene; Vinyl chloride Alcohols/78.5/31%/2 -butoxyethanol; Phenol; 1 -butanol Ketones/58.1/15%/Acetone Other(e.g. acetates,sulfides, ethers, etc.)/92.55/5%/Butyl acetate; Dimethyl disulfide; Ethyl acetate; Carbon disulfide; t-butyl methyl ether Conversion Factor In order to convert a PID reading from part per billion (ppb) to a mass-based equivalent in micrograms/cubic meter, the PID value is multiplied by a derived conversion factor, MCF, defined below as the product of two correction factors, CF-1 and CF-2. For the TVOC fingerprint listed above, the formula is MCF = CF1 * CF2, where MCF = 2.70 Mass Conversion Factor CF1 = 0.88 Correction for predicted ppb PID reading to "actual" ppb reading, based on isobutylene equivalents, and CF2 = 3.07 Correction for "actual" ppb to micrograms/cubic meter equivalent, based on the chemical distribution of the mixture and the average molecular weight. Summary The acceptance of this CIR would provide a lower cost test for TVOCs, including the use of both hand held PID-TVOC direct read instruments and permanently installed PID-TVOC direct read instruments.