Safety Toolbox Talk on Suspension trauma/ orthostatic intolerance

Safety Toolbox Talk on Suspension trauma | orthostatic intolerance

Safety Toolbox Talk on Suspension trauma/ orthostatic intolerance

Introduction

Suspension trauma is a condition of restricted blood circulation in the legs of person suspended in a Personal Fall Arrest System or especially in a full body harness after a fall from height.

Even after an individual is caught from a fall by a Personal Fall Arrester System, they are not out of danger. Within 15 to 20 minutes, suspension from a harness, causes blood to pool in the legs, eventually making the suspended individual pass out.  Leg straps of body harness squeeze the blood arteries of the thighs and thus cutting off blood circulation. The non-circulating blood in the legs then loses oxygen and becomes toxic, a dangerous condition known as suspension trauma, also known as Harness Hang Syndrome (HHS), or orthostatic intolerance.

Regulations – Suspension trauma/ orthostatic intolerance

OSHA 29 CFR 1926.502 gives guidelines on Fall protection systems criteria and practices.

Under OSHA, employers must prepare an emergency rescue plan to rescue workers in the event of a fall, whenever personal fall arrest systems are used. While preparing the fall rescue emergency plan, the availability of rescue personnel, ladders, or other rescue equipment should be evaluated. Employers must ensure a competent supervisor, and all workers working at height using the personal fall arrest system must be trained in rescue. To avoid further injury and avoid medical complications, emergency rescues must be performed promptly in accordance with 29 CFR 1926.502 (d) (20).

Body belts are not acceptable as part of personal fall arrest system according to OSHA 29 CFR 1926.502(b) because they can cause serious injury during fall.

Personal fall arrester system must be designed and setup according to OSHA 29 CFR 1926.502 (d)(16)(iii). Personal fall arrester system equipment must be certified by a competent person at intervals of every six months.

Hazards – Suspension trauma/ orthostatic intolerance

Crossing the safe endurance time: Waist belts are designed to be used as restraints only. They have an average of two minutes of endurance. Chest harnesses are designed for rescue and restraint and have an average of six minutes of endurance. Sub-pelvic full body harnesses average ten minutes of endurance.

Venous pooling: Due to free hanging on harness and load on leg straps, blood can accumulate in the veins. Also, it occurs when victim moves suddenly after being inactive for a long time.

Increase in heart-rate: Blood circulation rate reduced due to an accumulation of blood in the legs and then human body try to make up by speeding up the heart rate to supply sufficient blood flow to the brain.

Decrease the heart-rate: After 15 to 20 minutes of hanging, blood supply is significantly reduced, and then the body will abruptly slow the heart rate and blood pressure will diminish in the arteries.

Fainting: In case of severe venous pooling, oxygen deficient blood supply to the brain causes fainting. It can be occur due to low quantity supply of blood to brain.

Impact to other body vital organs: Reduction in blood supply may adversely affect the other vital organs, such as the kidneys.

Other hazards: Tremulousness, Palpitations, fatigue, nausea, poor concentration, dizziness, headache, weakness, sweating, etc.

Risk – Suspension trauma/ orthostatic intolerance

Prolong suspension in harness and in orthostatic intolerance, victim can cause fatality, damage of vital body organs or paralysis.

Because of unconscious or immobility of the legs, person may faint in static upright position and cause venous pooling. Psychological shock, other injuries, compaction by harness and other environmental conditions can lead to increase the onset and severity of the pooling and orthostatic intolerance. If workers in this condition are not rescued promptly, suspension trauma can result in fatal injury due to oxygen deficiency through blood circulation to the brain, kidneys, and other vital organs.

Controls and action plan - orthostatic intolerance

1. Emergency rescue plan to rescue workers in the event of a fall must be prepared prior to commencement of work at height with personal fall arrester system.

2. All engaged worker must be well trained on use of fall arrester system and must be supervised by competent supervisor.

3. All workmen must be aware about hazards and risk of suspension trauma/ orthostatic intolerance and they must know the basic controls to relax their body in hanging position followed fall.

 4. In the event of fall and free hanging in harness

a) Ask for help so that rescuer can respond

b) Try to regain nearest access to the structure, try to place your legs on structure to relax your weight on harness.

c) Try to pump your legs frequently to activate muscles and reduce the risk of venous buildup. Support points can be used to relieve pressure, delay symptoms and support muscle pumping.

d) Using Suspension Trauma Straps, which are a pair of straps, allows you to get up to relax your leg muscles by removing the load and restoring blood circulation until help arrives. When a worker falls and rests, he unwinds the straps, hooks them, and presses his weight against the straps.

Toolbox talk interacting Questionnaires

1. What is suspension trauma?

2. According to OSHA, could suspension trauma be fetal in how long?

3. What is the use of trauma strap?

4. How can the victim restore blood circulation in the condition of suspension trauma?

5.  How long does it take to cause suspension trauma after the fall event?

6. Can unconsciousness lead to fatality in the condition of suspension trauma?

7. What things should be considered when preparing the rescue plan?

Summary

The consequences of suspension trauma/  orthostatic intolerance can be severe if not promptly rescued, therefore proper training for workers on rescue plan is very important before using personal fall arrester system equipment.

The use of suspension trauma strap, use of nearby structure to relax the body weight on harness and the frequent pumping action of the legs frequently can activate muscles, reduce the risk of venous accumulation, can used to relieve pressure, delay symptoms, support muscle pumping and restore blood circulation.

A record of Toolbox talk on suspension trauma or orthostatic intolerance should be maintained.

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Safety Toolbox Talk on Suspension trauma/ orthostatic intolerance