User's Guide for the Texas Mobile Source Emission Estimation Software: PREPIN, POLFAC5A, COADJ, IMPSUM, and SUMALL (1279-2)

This research report represents the latest revisions to the software, PREPIN, POLFAC5A, COADJ, IMPSUM, and SUMALL. The report is presented as a user's guide; operating instructions are provided for each program. The mainframe programs were developed to estimate mobile source emissions and vehicle miles traveled (VMT). The PREPIN program allows the analyst to factor a 24-hour assignment to estimate the VMT and speeds for a subject time period. The POLFAC5A program is used to apply MOBILE5A to obtain emissions factors. COADJ, a special utility program, combines emission factors from three applications of the POLFAC5A program to produce a new set of emission factors. IMPSUM facilitates the computation of emissions by using the emission factors from POLFAC5A and COADJ. Lastly, SUMALL sums the emission results from two or more time periods plus diurnals. IMPSUM and SUMALL have the additional capability of producing gridded emission estimates.