The normal temperature of human urine ranges from 94°F to 96°F (about 35 °C). The temperature of drug test sample must be measured during first 4 minutes after it was received, as it changes depending on ambient temperature. Acceptable range is from 90 °F to 100 °F (32 °C - 38 °C) , any sample with a temperature out of this range will immediately fall under suspicion.