If you've worked in an environment where people are required to work at heights, you've probably heard the rule that once you're above 6 feet you must tie off. But what does this even mean? Tie what to where?
Generally, some form of fall protection or fall arrest must be used if an employee is required to work above the height of 6 feet off the ground, or in a position in which there is an unusual risk of injury from falling. Every company that requires work to be done at heights will have a fall protection plan. Some company's standards coincide with OSHA's fall protection regulations, and some exceed these regulations. OSHA's regulations require that a worker working at a height of 6 feet be required to use an appropriate fall protection system. OSHA standards can be found here: https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDSp_id=10757
If you are required to work at heights with an unusual risk of injury, the first step is to try to remove the hazard(s). Unusual hazards that might require fall protection precautions include protruding objects, unclear drop areas, etc..
The second step is to protect the fall, or prevent it from occurring. There are a variety of systems that can be used to protect workers from a fall. These types of systems are typically used when working near leading edges, or around holes and skylights. These systems include, guardrails, fences, barricades, and covers.
If the fall hazard cannot be protected using other types of fall protection, the next step is travel restraint. A travel restraint system allows the worker to travel far enough to work, but not far enough to fall off the edge. Typically, travel restraint is used in situations where there is a leading edge, though all fall hazards in the area must be assessed when using this type of system. Just because a fully extended lifeline will adequately restrain a worker in one area, does not mean that it will be effective in another area. The components of a travel-restraint system include:
- Full harness
- Rope grab
When setting up a travel restraint system, be sure to choose an anchor that will adequately support the potential force of load, and that it is positioned properly. Try to choose an anchoring area that is in the centre of the work area and as perpendicular to the unprotected edge as possible.
Fall arrest systems can include the following:
- Fall restricting / fall limiting system: A fall limiting or fall restricting system is designed to limit the free fall distance to 2 feet. These systems typically use the same components as a fall arrest system, though a sternal connection is used rather than the rear D-ring connection. These systems can be used in situations where the fall cannot be protected, and the worker is not at an adequate height to use a regular personal fall arrest system. Self-retracting lanyards are also included in the fall restricting category, as they can limit the fall, though not entirely prevent it from occurring.
Safety Nets: One of the leading fall protection systems in Europe is safety nets. Safety nets are systems designed by engineers, and installed below a work surface where a fall hazard exists. These nets can be used around the edges of buildings, on bridge work, or below formwork operations. Safety nets have become a popular choice in the construction industry because they eliminate the need for other types of fall protection equipment. Though they are expensive, they save on the cost of other equipment, and save time, as this type of fall protection only requires to be set up once, rather than each shift. Click the link below to see how safety nets can be constructed around the exterior of a building: https://www.youtube.com/watch?v=rwvmru5JmXk
Personal Fall Arrest System: A fall arrest system consists of the following components:
- A full body harness
- A lanyard, typically with a shock absorber
- The harness must be connected to an adequate fixed support, whether it is by lanyard, or lanyard and lifeline
- Appropriate anchorage capable of withholding the potential force of the falling load
There are three basic types of lifelines available for use with fall arrest systems:
- Vertical lifelines - Vertical lifelines are so-called because they are positioned overhead, thus the lanyard or lifeline falls vertically. Workers can move up and down the length of the lifeline. These systems are typically used in conjunction with rope grabs and on vertically moved work surfaces such as swingstages
- Horizontal lifeline - Horizontal lifelines are typically comprised of a line that allows the worker to move horizontally across a work surface. Usually, the line runs horizontally and the worker attaches to the line via a lifeline or a lanyard
- Retractable lifelines - Retractable lifelines are designed to limit falls by employing a locking mechanism that allows the line to unwind off of the drum as the worker moves around the work area, but automatically locks with quick movement such as a fall
There are three basic types of anchorage used in fall protection:
- Designed fixed support - purposefully designed and permanently installed for protection. This can include anchors that have been built into the structural design of the building, such as roof anchors
- Temporary fixed support - This includes anchor systems that are designed to be connected to a structure using specific materials and methods
- Existing structural features or equipment - this includes areas that are not intended or designed to be anchor points, but are verified as having adequate capacity to serve as anchor points. This can include structural steel, or reinforced concrete columns, etc.
Designed fixed supports can be used to anchor a fall arrest system, or travel restraint system if the support has been installed according to code, and is safe and practical to use. Generally, any temporary fixed supports must be capable of supporting at least 5, 000 pounds per employee attached. OSHA minimum standards vary depending upon what system is used, so be sure that the anchor system you choose is appropriate to the type of fall arrest system.
Full Body Harness
Fall restricting and fall arrest systems both use a full body harness as an essential component of the system. For a harness to function as an effective component of a fall arrest system, it must be worn and adjusted properly. When fitting your harness, ensure:
- The chest strap should be adjusted so that it sits in the middle of the chest, and is snug. In the event of a head first fall, the chest strap prevents the individual from falling out of the harness
- Leg straps should be adjusted snugly so that no more than one hand may fit between the strap and leg
- The harness should be adjusted so that the D-ring sits in the middle of the back between the shoulder blades. In the event of a fall, a properly adjusted D-ring will keep the individual upright
- Before each and every use, be sure to inspect the entire harness for signs of damage (burns, cuts, etc..), loose or broken stitching, frayed material, grommets and buckles are free of damage and distortion
Safety lanyards are an essential element of a fall protection system. Without the lanyard, a full body harness is useless in arresting a fall. There are a variety of different types of lanyards available, each with its own specifically designed use. Depending on what type of lift you are using and how high above the ground surface you are working, your lanyard choice will vary.
Generally, the most common types of lanyards include:
- Shock absorbing lanyard: These lanyards have a built in shock absorber that expands in the event of a fall, which minimizes the force felt by the individual
- Double legged lanyard: These types of lanyards have two straps rather than the usual one. They are typically used in situations where one lanyard does not allow the worker a sufficient length to do the work and the worker must vary the anchor point. The double strap allows the worker to move anchor points while being attached at all times. These are also commonly used with horizontal lifelines
- Adjustable lanyard: These lanyards have adjustable straps, so the length of the lanyard is made variable. These are typically used in situations where the working height changes frequently, such as in a boom lift
- Retractable lanyard: These types of lanyards, as discussed above, allow enough slack while working by unraveling from the spool device as the worker moves, but lock with any quick movement, thus arresting the fall
- Lanyard (dog leash): These lanyards are essentially the same as a shock absorbing lanyard, but without the shock absorbing pack. They are used in areas like scissor lifts, where it limits the ability of the worker to fall out of the machine in the first place. The lanyards functions as a fall restrictor, thus the shock absorber is not needed
Fall Arrest Planning
Fall arrest planning will determine what type of fall protection or fall arrest system is necessary for the job. Planning includes assessing the job site and the potential fall hazards, where and how the workers might possibly fall, anything that they might encounter during a fall, and at what height the worker is working at from the next surface level. The total fall distance is the distance required to fully arrest a fall, and must be considered when choosing a fall arrest system. Total fall distance includes:
- Free fall distance, which should be kept under 1.5m or 5 feet
- Fall stopping distance, which should allow for the stretch in the lanyard or lifeline (minimal), slack in the harness (maximum 1 foot), and the deployment of the shock absorber (maximum 1.1 metres)
The free fall distance is measured from the D-ring of the standing worker to the point at which the lanyard or shock absorber begins to arrest the fall. Free fall distance should be kept as short as possible. This can be minimized in several ways, including using as short a lanyard as the work allows.
Before a fall protection or fall arrest system is used by anyone, there first must be a written rescue plan and procedure set in place. The plan must account for simple rescues as well as complicated ones. All workers must receive training regarding what to do in the event of a fall. The plan should cover the on-site equipment available, personnel and procedures for different types of rescue.
Off-site rescue services should be contacted and arranged in advance. The appropriate contacts, addresses, routes, and phone numbers should be posted somewhere where employees can view them easily and clearly. Coordinating with local rescue squads will allow you to know approximate ETAs in the event of an emergency, so the fall protection plan can be tailored to suit the circumstances. An example of this would be to have employees carry trauma straps if the expected ETA of a rescue team is over 5 minutes.
It is essential that site management ensure that:
- All employees on site are aware of the rescue plan
- Equipment and resources are made available
- Designated personnel are properly trained
Remember, take your time choosing the right fall protection system. Assess the hazards and your environment thoroughly before deciding on what system is best. Be sure that employees are well trained in how to use the equipment, and what to do in the event of a fall.