This is a study to look at the effect on breathing of various ways to package a person in a rescue litter. We will measure lung function in a litter, lying down, lying down in a vacuum mattress, one the side in a vaccum mattress, and vertical in a vacuum mattress.
Subjects must be 18 to 65 years old. Per the harness manufacturer's recommendation, participants must weigh between 130 and 300 pounds and have a waist between 32 and 42 inches.
Weight greater than 300 pounds or less than 130 pounds, pregnancy, any known heart condition or murmur or lower extremity edema or wheezing detected on pre-participation exam, or a waist size <32" or >42". Prior to suspension, female participants of childbearing potential will self-administer an FDA approved urine pregnancy test supplied by the investigator. Results will be verified by the investigator.