The bioburden of the commercial adhesive bandage with gauze pad was investigated in order to estimate the sterility dose setting of this item.The distribution of the contaminated microbes on a strip were determined with 1,258 strips of bandage sampled from 12 lots of the products. It was found that the maximum and minimum of the contaminants per strip was 11 and 0,respectively, and the average per strip was 2.65. Besides, no significant differences in the distibution of the numvers of contaminants per strip among the lots were observed.From strips of 5 lots, 235 isolates were obtained and subjected to the taxonomic tests. Most of them were bacilli, of which Bacillus pumilus was predominant. The D value of each strain of 147 isolates sampled from 3 lots, was determined after the irradiation of the prepared test pieces and the D value distribution with microbial population was calculated. The highest D value, 0.19 Mard was obtained with some strains of B. pumilus and B. megaterium. In the comparison with the D values of indicator microbes, B. pumilus ATCC 27142 loaded on the parts of the bandage or on the test pieces, the maximum D value MAXD 10 was assumed to be 0.22 Mrad. Sterility tests of the intact bandages were also carried out after irradiation at incremental doses.From the results obtained, sterilization dose SD was estimated at 1.76 Mrad according to the formula SD=D×log (No/N), on the other hand, according to four methods described in AAMI recommended practice, SD was estimated at 1.52 Mrad, 1.52 Mrad, 1.28 Mrad and 1.33 Mrad, respectively.In the estimations above, it is supposed that 10^<-6> of sterility assurance level of this bandage is attained at the dose less than 2.0 Mrad.

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