Why do workers suspended in a full body harness often lose consciousness after a fall?

When workers are suspended in a full body harness after a fall, the primary reason they may lose consciousness is due to restrictions in blood flow to the extremities caused by the harness. When someone falls and is caught by a harness, the sudden stop can create pressure points, particularly around the thighs and groin, which can impede circulation. This pressure may lead to restricted blood flow, resulting in a decrease in oxygen supply to the brain. If the brain does not receive adequate oxygen, loss of consciousness can occur.

The design of the harness itself can contribute to this issue, as it is meant to secure the individual during a fall; however, if the person remains suspended for too long, the body's position and the pressure exerted by the harness can lead to serious physiological consequences, including fainting or loss of consciousness.

Other factors, such as dehydration or head trauma, can certainly impact a person's ability to remain conscious but are not the direct causes linked to the mechanisms of suspension trauma in this scenario. Similarly, the neck whipping motion associated with a fall can result in injuries, but it does not primarily cause loss of consciousness like the restriction of blood flow does.