The present study demonstrates the differences in the quality of roof runoff from bitumen shingle and galvanized iron test roofs. Average first flush conductivity was found to be 113.6 μS/cm in bitumen roof runoff as opposed to 45.4 μS/cm in galvanized iron roof runoff. The chemical oxygen demand of bitumen roof runoff was one order of magnitude higher than that of galvanized iron roof runoff, which could be attributed to the material and coarse surface of the former roof. The suspended solid content of the two runoffs there were, in average, identical.
The manganese content of some industrially important steel samples viz. IS-226, spring steel, galvanized iron, high tensile steel, and mild steel is determined by instrumental neutron-activation analysis using a252Cf neutron source. The analysis is performed by measuring the activity of56Mn after /n, / reaction on a 4 k multichannel analyzer coupled to a NaI/Tl/ detector at 847 keV, as well as on a single channel analyzer on integration mode coupled to a NaI/Tl/ detector. The results obtained by both procedures show reasonably good agreement with each other.