When you're working with any kind of fall arrest system, you need to keep your friends close, and your coworkers closer. Even if you have the top-of-the-line system, you're never permitted to use it alone, because you need somebody else on site to ensure rescue procedures can be carried out.
According to the WHSQ Code of Practice:
"A PCBU who implements a fall arrest system as a control measure must establish emergency and rescue procedures. The emergency and rescue procedures must be tested to ensure that they are effective, and workers must be provided with suitable and adequate information, training and instruction in relation to the emergency procedures. The rescue of a worker who is suspended in a full body harness should occur promptly to prevent suspension intolerance and to treat any injuries sustained during the fall and fall arrest. A worker should not use a fall arrest system unless there is at least one other person on the site who can rescue them if they fall."
There are multiple reasons as to why workers should not work alone, but one of the major ones is suspension trauma.
Suspension trauma, also known as suspension intolerance or orthostatic shock, has been reported to affect victims who are suspended within a body harness for a prolonged period of time (5 to 30 minutes). It may result in loss of consciousness or death. This is thought to occur as a result of low blood pressure due to blood pooling in the legs combined with an increase in the activity of a part of the nervous system that slows the heart (vagal tone).
The signs and symptoms of suspension trauma are the same to those of shock. Suspension trauma should be considered where the victim has been suspended by a harness for a prolonged period, and is exhibiting any of the following symptoms:
- feeling faint or dizzy
- breathlessness
- sweating
- looking pale
- nausea
- low blood pressure
- loss of responsiveness
Those exhibiting symptoms can easily - and without warning - progress to later stages of suspension trauma within a few seconds, meaning that any symptom should be treated with the utmost caution. Individuals should be removed from the suspension as quickly as possible, if it is safe to do so, to minimise the effects of suspension trauma. It is highly recommended that an ambulance is called whenever there is a risk of any person suffering from suspension trauma, even in the event of an expedited rescue. Injuries as a result of trauma can be invisible and may have a delayed on-set, and the advice of medical professionals should always be followed.
Even after being removed from the harness, any person who may have suffered suspension trauma should be placed in a horizontal or supine position for recovery, as there can still be serious health effects when the pooled blood returns to the body, or as a result of any number of things that can occur during a height safety incident. It should be noted that some advice used to state that suspension trauma victims should be placed in a sitting position upon rescue, rather than being allowed to lay down. However, this is not true, per the ANZCOR Guidelines, and following this outdated advice may prove harmful.
The exact mechanics of suspension trauma and recovery are unknown, as research in the field is limited, and testing suspension trauma's effects on a person without actually endangering them is incredibly difficult. As such, guidelines in this field are prone to changing, and you should always defer to the most up-to-date medical advice whenever available, particularly if it conflicts with the information here. None of the information in this article constitutes as medical advice and should not be treated as such.
Suspension Trauma Straps:
Suspension trauma straps are designed to minimise (and hopefully prevent) the effects of suspension trauma without interfering with the efficacy of the fall-arrest system. These straps, often deployed at the waist, create loops attached to the harness which drop down below the worker and provide a surface to 'stand', placing weight on the legs and stimulating the muscles, improving blood flow.
Some harnesses also incorporate these straps into their basic design, with integrated suspension trauma straps included to protect the worker in the case of a fall. While it is possible to stimulate the muscles without these straps - through small bicycle kicks or other motions with the legs while hanging - these straps are medically proven and recommended as consistent and effective methods to delay suspension trauma.
Other Injuries:
Although it may be obvious to some, it's still entirely possible to get injured even if all parts of your safety system work correctly. The forces involved in a fall from heights are so severe that even a small item can prove deadly, and that power does not go away when something much larger and heavier, such as a person, is dropped from a height. Any collisions on the way down can - and will - seriously injure somebody, and an unfortunately-timed bump could knock someone out cold, leaving them to dangle helpless in their harness.
Due to this, self-rescue systems, while often very helpful and potentially life-saving, are not the be-all end-all for height safety management. Although the implementation of self-rescue systems into height safety equipment is incredibly beneficial, there is still always a requirement for workers to have a potential rescuer on-site and aware of the situation.
