A certain disinfectant has a decimal reduction time of 100 seconds. When used to completely disinfect...
A certain disinfectant has a decimal reduction time of 100 seconds. When used to completely disinfect a surface conatining 1 x 10^6 bacterial cells, how long must the surface be soaked in the disinfectant?
Homework Answers
Decimal reduction time is the time taken by a particular disinfectant at a certain concentration to kill 90% of the bacteria on the surface. Thus, only 10% of bacteria will remain after exposure to DRT. Hence, a surface containing 1 x 10^6 bacterial cells must be soaked in the disinfectant for 700 seconds. This is obtained by adding 1 to the exponent of 10 and then multiplying it by DRT. (6+1 = 7 x 100 = 700 seconds) Thus 700 seconds is the soaking time for this particular disinfectant in the question.
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A certain disinfectant has a decimal reduction time of 100
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