"Normal conditions" refers to the usual or typical state of something where everything is expected to be functioning or occurring regularly without any disruptions or abnormalities. Full definition
Under normal conditions in healthy individuals, 20 to 30 mg a day for women and 6 to 10 mg a day for men is considered a physiological amount. (drlam.com)
In normal conditions of use, it is difficult to see any change in the bottle over the first week of use. (feliway.com)