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SRD-Source Ranking Database User's Guide and Documentation, Vol. 1 and Vol. 2

The purpose of the SRD is to provide a means for systematically reviewing a large number of
consumer products, building materials, and furnishings that are potential sources of airborne chemicals to
which individuals can be exposed while indoors. The software is intended for use as a screening tool, to
identify high-priority products or product classes for further evaluation. There are three applications in SRD:
(1) ranking products on the basis of acute or chronic hazard ratings, (2) finding products that contain a
particular chemical, and (3) identifying the chemicals found in a particular product.

The primary application in the SRD software scores and ranks products and materials using modeled
indoor-air concentrations of their chemical constituents in selected types of environments, frequency of use
(in the case of products), the fraction of buildings in which products or materials are used, and the relative
health hazard associated with inhalation of each chemical. The size of potentially exposed populations in
each environment is also taken into account. Products and materials can be ranked based on peak modeled
concentrations and acute chemical hazard ratings or time-integrated concentrations together with chronic
hazard ratings for chemicals.

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