Long snorkel: inhalation of a breath occurs when the muscles surrounding the human lungs move to increase the volume of the lungs, thereby reducing the air pressure in the lungs. the difference between the reduced pressure in the lungs and outside atmospheric pressure causes a flow of air into the lungs. the maximum reduction in air pressure that muscles of the chest can produce in the lungs against the surrounding air pressure on the chest and body is about 3740 pa. consider the longest snorkel that a human can operate. the minimum pressure difference needed to take in a breath is about 188 pa. find the depth h that a person could swim to and still breathe with this snorkel