The minute dose of ozone delivered to the lower respiratory tract of a subject depends upon the ozone concentration inhaled, the minute volume (Ve 1/min) and the fraction of the inhaled ozone that penetrates the nasopharyngeal passages to enter the trachea. The ozone concentration (X) depends on the time of day and whether the subject is indoors or outdoors. The minute volume depends on the subject's age, sex, weight, and physical activity level. The fractional deposition of ozone depends on the concentration inhaled (X), the minute volume (Ve), and the mode of breathing (nasal or oronasal). These dependencies are reviewed and a calculation of a daily ozone dosage is presented for a prototypical 12-year old child at summer camp who varies his physical activities in indoor and outdoor settings over a 24-hour period.