The pressure relieving characteristics of an alternating pressure mattress are compared to the characteristics of a traditional hospital mattress. The trochanteric pressures of 20 healthy volunteers had a mean of 95 (SD = 49) on a hospital mattress while the trochanteric pressures on the alternating pressure mattress had a mean of 67 (SD = 9) for the inflated cells and a mean of 23 (SD = 7) for the deflated cells. Statistical analysis revealed significantly lower interface pressure for the alternating pressure mattress.