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Safety Toolbox Talk on Personal Fall Arrester System (PFAS)

May 30, 2021 ,

Safety Toolbox Talk on Personal Fall Arrestor System (PFAS)
Toolbox Talk on Personal Fall Arrestor System (PFAS)

Safety Toolbox Talk on Personal Fall Arrester System (PFAS)




Introduction
A Personal fall arrestor / protection system is required when working at height levels with an unprotected side or edge. When it is not possible to provide a safe working platform, i.e. secured full deck board with guardrails including toe guards and means of safe access and there is risk of fall from height, then use of personal fall arrester or personal fall protection equipment is mandatory.
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In addition, personal fall protection equipment must be worn by people who work on mobile working platforms such as man basket, cradle, and cherry pickers, etc.
Appropriate connectors assembly along with full body harness required for each work shall be determined based on the level of exposure, nature of work, type of roof/surface/platform, etc. and shall be listed in the permit to work.
Generally, a personal fall arrester system consists of anchors (connector), full body harness and lanyard with shock absorber.

Regulations – Personal fall arrester system

OSHA 29 CFR 1926.502 gives guidelines on Fall protection systems criteria and practices.
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.
When workers are exposed to fall of 6 feet or more to a lower level, they must wear personal fall arrester. Personal fall arrester system must be designed and setup according to OSHA 29 CFR 1926.502 (d)(16)(iii).
Complete personal fall arrester system must comply OSHA 29 CFR 1926.502 (d) (15) requirements and the anchorage with anchorage connectors of fall arrester system must be capable to withstand the load of 5000 pounds per worker.
Personal fall arrester system equipment must be certified by a competent person at intervals of every six months.

Hazards – personal fall arrester system (PFAS)

Here are the main hazards associated with personal fall arrester system
Defective PFAS equipment: Defective equipment can be prone to fail and may lead to serious injury. Damaged, uncertified,  inadequate setup of fall arrester system can create hazards.
Unsafe practices: Failure to anchor the personal fall arrest device while moving from one point to another can cause serious injury. Even when worker anchors the fall arrester wrongly at lower level may be liable to sustain injury due to jerk of falling force.
Incompetence: Incompetent worker are vulnerable to violate the safety rule and control measures.
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.

Risk – Personal fall arrester system (PFAS)

Suspension trauma: Even after an individual is caught from a fall by a fall arrest system, they aren’t 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. 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.
Since the performance and practice of the personal fall arrest system depend on human competence and behavior, there is a risk of non-compliance, which can lead to serious injury.

Safe work practices and controls

1. Plan and organize the work in advance through the work permit system and the Job Safety Analysis to assess the requirement of personal fall protection system.
2. Make sure, all personal protective equipment used for working must be certified and inspected before use.
3. Workers must be trained in the use of personal fall arrester equipment and must work under the constant supervision of a competent person.
4. Workers with health problems such as heart disease, high blood pressure, psychosis, epilepsy, or one of these diseases should be considered unfit.
5. It is very important to calculate the proper length of lanyard, anchorage position and the distance to the lower level i.e. fall clearance distance to prevent contact with lower surface in the event of fall.
6. The pendulum effect must be predicted for the fallen worker so that it cannot be hit on the nearby structure. There anchor point must be above the work area.
7. The vertical distance between the worker and lower level is called as total fall distance and it is determined by considering below points
a) Free fall distance – worker falls before activation of PFAS. This distance must be less than 1.8 meters.
b) Deceleration distance – lanyard length in stretched condition to arrest the fall. This length/ distance should not be more than 1 meter.
c) D-Ring shift – to support the full weight of fallen worker with tools, D-ring shifts and stretches the harness. This distance is generally considered as 1 foot.
d) Back D-ring height – It is the length/ distance between D-ring and the sole of worker’s footwear. Generally, it is considered 1.5 meters but may vary person to person as per their height and must accordingly adjusted.
e) Safety Margin – To ensure enough clearance between the worker and the lower level after fall, a additional distance should be considered and this is called as safety margin. Generally, it is considered 2 feet.
Total Fall clearance distance is the addition of all above factors.
8. A personal fall arrester system includes an anchorage (where the lanyard’s snap hook is attached), Full body harness and connector i.e. lanyard with shock absorber or lifeline. Connector couples the body harness to the anchorage. Lifeline may be self-retractive type or with deceleration device.
9. How to wear full body safety harness properly:
- Before use, inspect your harness for any damaged straps, buckles, D-ring and lines. Always follow the manufacturer’s instructions and keep in mind that most of the harness are withstanding 140 kg load.
- Hold the harness by D-ring in your right hand and shake it to allow all straps to hang down. If any strap i.e. chest, thighs or waist are already buckled then unbuckle them before wearing.
- Slip straps over shoulders and ensure the D-ring of harness at center i.e. between the worker’s shoulder blades. Lanyard should be attached to the D-ring.
- Adjust the harness to fit comfortably. Make sure all straps are fastened and adjusted correctly.
- The leg straps should be adjusted until they are comfortable, its should not be so tight, to check it put the palm of hand into the straps across the thighs so that it should be comfortably fitted. There should be a gap of about one inch between your thighs and straps. Connect waist strap after leg straps.
- Ensure shock absorber fitted with lanyard
10. Lanyard anchor must be secured with anchorage point which should be strong enough to withstand the load of worker with safety margin. During roofing work, do not attach anchors to sheathing, single trusses or guardrails as these may not designed or strong enough to hold the load of falling workers. Anchors can be attached to a structural member or truss member.
11. The lifeline can be used to move from one point to another. A horizontal lifeline can be attached to the overhead structure which helps the uninterrupted protection while working. Self-retracting lifelines enable greater horizontal and vertical mobility than traditional 6-foot shock-absorbing lanyards.
12. Fall protection system can be combined with safety warning line system or with safety monitoring system.
13. All workers must know about what to do in the event of emergency i.e. fall. In case of emergency fall,
- ask for help,
- try to regain nearest access to the structure, try to place your legs on structure to relax your weight on harness.
- 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.
- 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 meant by total fall clearance distance?
2. What to inspect before wearing full body harness with connectors?
3. Does the full body harness help prevent falls or minimize the fall distance?
4. What is meant by ‘lifeline’ and when does it require?
5.  What is Suspension Trauma?
6. Why do you require personal fall arrester?
7. What is the frequency of certification for PFPS equipment?
8. What is meant by Self-retracting lifelines?
9. What will you do in case of a fall and hang up on PFPS?
10. How to check the comfort of the body harness?

Summary
The consequences of failure of a Personal Fall Arrest System (PFAS) can be serious, therefore proper selection, inspection and training for workers is very important before use. Working at height without a proper work platform and without guard railings is the most dangerous job because it presents a high risk of serious injury.

An appropriate personal fall arrest system with an appropriate risk assessment, work permit, best practice adoption and competent supervision must be implemented. A record should be kept of the Toolbox talk on Personal Fall Arrest System.

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