Suspension trauma occurs when the leg straps of a personal fall arrest harness constricts the flow of blood through the veins, resulting in blood pooling in the lower extremities. Lack of motion in an upright position is the main cause. When blood pools in the lower extremities, the heart and brain do not get sufficient blood to function properly, which results in fainting. If the person were standing, the fainting (in a horizontal position) would correct the situation by allowing the pooled blood in the legs to reach the heart - now on the same level. When a person is suspended in a harness and loses consciousness, the harness keeps the person in an upright position and the situation does not correct itself. The longer a person is suspended in an upright position, the higher the risk for suspension trauma and possibly death. Prompt rescue is imperative.