A suspension relief strap is a compact, deployable safety device integrated into a worker’s full-body safety harness. It is designed to be used immediately following a fall to aid the worker while suspended in mid-air. The strap acts as a temporary foothold, providing a way for the worker to relieve pressure and maintain circulation during the time spent waiting for a rescue. This accessory is a measure against a serious post-fall medical threat.
The Risk of Suspension Trauma
The suspension relief strap is designed to counter suspension trauma, a physiological condition also referred to as orthostatic intolerance or harness hang syndrome. This life-threatening condition occurs when a worker remains suspended motionless in an upright position in a harness. Gravity and the pressure from the harness’s leg straps compress the major veins in the groin area.
When blood cannot return to the heart, it pools in the legs, a process known as venous pooling. The pooling blood is deprived of oxygen and becomes toxic with metabolic waste products. This reduction in circulating blood volume means less oxygenated blood reaches the heart and brain, triggering a drop in heart rate and blood pressure.
Symptoms such as lightheadedness, nausea, dizziness, and sweating can appear in as little as a few minutes. If not quickly addressed, the worker can lose consciousness, increasing the risk of death from cerebral hypoxia, or lack of oxygen to the brain. Fatality can occur quickly, sometimes in 10 to 15 minutes, emphasizing the urgency of a prompt rescue.
Components and Placement of the Strap
The suspension relief strap is a lightweight, compact accessory that attaches directly to the body harness. It is often packaged in small pouches secured to the harness webbing near the waist or hips. This placement ensures it is easily accessible to the worker after a fall, even while suspended.
When deployed, the strap unravels into a length of durable webbing, sometimes forming a continuous loop or a bridged-style stirrup. Some systems use two separate packs that connect together in front of the worker to form the foot support. The worker deploys the strap, often by pulling a small tab, to create a stable foothold.
How the Strap Prevents Injury
Once the strap is deployed, the suspended worker steps into the loop, creating a temporary platform to stand on. This action immediately shifts the load-bearing pressure away from the leg and groin straps of the harness. By transferring the worker’s weight to the skeletal structure of the legs and feet, the strap relieves pressure on the femoral arteries and veins.
Relieving this pressure directly counters the blood pooling associated with suspension trauma. Standing in the strap also allows the worker to actively move or “pump” their leg muscles, simulating walking or pedaling. This muscle contraction helps push deoxygenated blood back up from the legs toward the torso, facilitating venous return to the heart.
Using the strap buys the worker precious time while awaiting rescue by mitigating the rapid progression of orthostatic intolerance. The ability to stand and move the legs significantly extends the period a worker can safely remain suspended, ensuring they are in better condition when rescue personnel arrive.