Statistical Summary And Trend Evaluation Of Air Quality Data For Cleveland Ohio In 1967 To 1971 PDF Download

A major objective of air quality monitoring is often to determine compliance with air quality standards, which may in part consist of a 24-hour level not to be exceeded more than once a year. Calculational procedures are critiqued for estimating the corresponding ambient pollution level when a sampling program is operating in conformity with EPA guidelines, that is once every 3 to 6 days. Quantitative consideration is given to the questions of the statistical independence of the data, the commutativity of expectation and exponentiation operations, and the statistical variability of the calculated results. Monte-Carlo simulations indicate a 95-percent confidence interval of + or - 56 percent at 60 samples per year and + or - 40 percent at 120 samples per year. Based on these calculations, sampling frequencies of every third to every sixth day are inadequate for determining conformity with standards expressed as levels not to be exceeded more than once per year.