You can accumulate hours over a threshold using the MAX function. The first formula below returns any hours over 8, or 0 if there weren't any such hours. The second formula returns any hours over 2, or 0 if there weren't any such hours. These formulas assume that you are using whole numbers to represent the hours.
If you are using times like 6:45 in cell B2, then the formulas would be slightly different: