a survey on tehran atmospheric polutants particulate matter & sulfur dioxide

particulate matters commonly found dispersed in the atmosphere are composed of a large variety of substances. dustfall is the usual index of particles in the size range greater than 10 m. two semi automated so2 sampling units were installed in tehran university campus (from 21 january 1973 to 22 dec. 1974) and gheitarieh area (from 23 august to 23 oct. 1974) hydrogen peroxide method was used for analytical procedure, and arithmetic mean was calculated as monthly average indicator. the results showed the yearly arithmetic averages of so2 in university campus, and three months arithmetic averages of gheitarieh area were 716.854 and 77.72 /g/m3 that means 13.7 and 1.48 fold greater than the maximum allowable concentration of u.s. 1971 standard respectively.