The need for an appraisal of the potential contribution of organic solvent usage to the photochemical smog problem in Los Angeles County had gradually become apparent and was confirmed by the results of surveys to determine the kinds and quantities of solvents used. The need for control of emissions resulting from various uses of organic solvents could be determined only by investigation and evaluation of the relative photochemical reactivity of such emissions The studies and criteria utilized to assess both such needs are described as well as the sresults of the studies into a functional, purposeful rule for the control of organic solvent emissions.
