Believers often encounter difficulty in getting enough water to purify themselves beyond the urinary orifice when using public restrooms where faucet water is not available [near the toilet]. Thus, for example, is it permissible to purify oneself from feces by wiping with toilet paper?
The urinary orifice must be washed with water once in order to purify it, and should be washed twice, or even three, times as a recommended precaution. As for the fecal orifice, it can be purified by wiping it once with any object (such as a cloth, tissue paper, or something similar) that will remove the impurity, provided the impurity does not spread beyond the orifice. If the impurity spreads to other parts of the body (i.e., surrounding the orifice) then water must be used to purify.