This training session provides important information on fall protection at construction sites. Anyone who is exposed to potential fall hazards must

Transcription

1 This training session provides important information on fall protection at construction sites. Anyone who is exposed to potential fall hazards must be trained to identify these hazards and how to properly use fall protection. Note that this training session covers general fall protection topics but does not discuss certain specific activities covered by the Occupational Safety and Health Administration, or OSHA, regulations, such as stairways, ladders, electric power lines, and steel erection work. 1

2 The objectives of this session include being able to: Recognize fall hazards and identify when fall protection is needed; Use basic fall protection systems; Prevent objects from falling; Inspect personal fall arrest systems; and Rescue yourself and others from falls. 2

3 Statistics on falls show how important it is to understand fall protection. Falls are the leading cause of fatalities in the construction industry. About 700 workers in all U.S. industries are killed by falls each year. About 100,000 construction workers are injured by falls each year. And 40% of construction industry injuries are related to falls. 3

4 Fall protection regulation is the responsibility of (*) OSHA under the Code of Federal Regulations Title 29, Sections to Construction sites are covered by these regulations. The regulations protect all workers at construction sites who might be exposed to fall hazards. You must be trained to recognize fall hazards and to follow training procedures to minimize fall hazards. However, scaffolds, cranes and derricks, steel erection, tunneling, electrical transmission, and ladders and stairways are not covered in these particular regulations or this session. 4

5 There are a number of requirements for employers to take precautions to guard you against fall hazards. These include: Assessing site conditions to determine where workers might be exposed to fall hazards, such as leading-edge work, holes in the floor, openings in walls (including large windows), excavations, and other potential hazards. Selecting fall protection systems that are appropriate for each potential fall hazard. Installing fall protection systems that have been selected. These must be properly constructed and may require special engineering and design. Following safe work procedures that are developed to protect against fall hazards on the site. Finally, training workers in the proper selection, use, and maintenance of fall protection systems. 5

6 It s important to recognize free fall hazards that is, potential falls from a higher elevation to a lower elevation because these cause the most serious injuries and can occur anywhere, at any time. Examples of freefall hazards include: Edges of platforms, stairs, and other working surfaces; Sloping surfaces, such as a roof; Ladders; Holes or openings, including skylights; and Tools and equipment falling onto workers or workers falling onto equipment. The photograph on this slide shows a broken skylight where a roofer sat on it and fell through to his death. 6

7 When is fall protection needed? You must be protected from potential fall hazards under these conditions: Whenever you are working 6 feet or more above a lower level. When there is a hazard of falling into dangerous equipment, even if the equipment is less than 6 feet below you. That s because the dangerous equipment may be more of a hazard than the fall. Certain specific areas or activities identified in the OSHA regulations. These include ramps, runways, walkways, excavations, hoist areas, holes, formwork and reinforcing steel, leading-edge work, unprotected sides and edges, overhand bricklaying, roofing work, precast concrete erection, wall openings, and residential construction. Finally, fall protection is required when walking and working surfaces are being inspected to make sure they are strong enough. 7

8 Do you understand the hazards of falls and fall protection requirements? It is time for you to ask yourself if you understand the material presented so far. It is important for your safety that you understand how to protect yourself against falls. 8

9 Fall protection systems are of two primary types: Fall prevention, or restraint, systems. These keep you from falling in the first place. A guardrail is an example of a fall restraint. Fall arrest systems are types of equipment that stop a fall in progress. A harness, such as the one shown here, is an example of a fall arrest device. 9

10 Falls can be prevented by following certain safe work practices and using equipment that prevents falls. Here are some safe work practices to follow when working near potential fall hazards: Keep the work area clean, neat, and orderly. A work area cluttered with materials, tools, and equipment could result in a worker tripping and falling to a lower level. Look around you, and be aware of your surroundings. Know where the nearby fall hazards are located. Listen to verbal warnings you may be approaching a fall hazard without knowing it. Pay attention when a coworker warns you of a hazard. Use fall protection for every fall hazard, and don t go near a hazard unless some form of fall prevention system is in place. Avoid dropping objects such as tools and materials to the level below you. Someone below you could be killed or seriously injured. Finally, never run when working at a high elevation. Running makes it easier for you to trip or lose your balance. 10

11 Here are some important fall prevention systems and practices commonly used to prevent falls at construction sites: Positioning device systems, or anchored harness; Guardrails; Warning line systems; Safety monitoring systems; Controlled access zones, or CAZs; Covers; and Protection from falling objects. We ll discuss these in more detail in the next few slides. 11

12 A positioning device system with a harness is a very effective device for both restraining and for arresting falls. It is commonly used when working close to an unprotected edge or on a slope, such as a roof. The harness is connected by a lanyard to an anchor. When a harness is anchored in this way, it is a fall restraint system. This system allows movement around the worksite. It prevents you from going off the edge because the length of the lanyard can be adjusted. 12

13 Guardrail systems are seen very often on construction sites. They are the most common protection used to restrain workers from falls off ramps, runways, walkways, unprotected sides and edges, and wall openings, as well as falls into excavations, holes, and hazardous equipment. Top rails must be able to withstand a 200-pound force applied in an outward or downward direction. Top rails also must be 39 to 45 inches above the walking or working surface. Steel or plastic banding is not acceptable for rails, but manila, plastic, or synthetic rope can be used as long as it is inspected regularly to make sure it remains strong and stable. Midrails must be able to withstand a 150-pound force. They must be installed halfway between the top rail and the walking or working surface. If screens, mesh, or panels are used instead of midrails, these must extend all the way from the top rail to the surface. Toeboards must be installed and must be strong enough to withstand a 50-pound force applied in an outward or downward direction. 13

14 Here are some other important features of effective guardrail systems: They must be smooth, with no projections. They should not present a danger of puncture wounds or lacerations or the possibility of snagging clothing. The ends of rails cannot hang out over the posts or project out into the walking or working surface. A fall arrest system is required whenever guardrails are removed. For example, at hoisting areas, a chain, gate, or removable guardrail section must be placed across the access opening when hoisting operations are not taking place. During hoisting operations, when the access opening is not protected, workers must be protected from falling by using personal fall arrest systems. Guardrails must be installed on all unprotected sides around holes, excavations, and ramps. Holes, including skylights, may also be protected by covers. When holes are used to pass materials from level to level, two sides of the guardrail system may be removable. However, when holes are used as access for people, there must be a gate in the guardrail system around the hole. Now let s look at other types of fall restraining systems. 14

15 A warning line system is used for relatively large, open elevated areas. The warning line warns workers to stay a safe distance away from fall hazards, such as a leading edge or roofline. These systems consist of ropes, wires, or chains. The material selected must have a minimum tensile strength of 500 pounds. However, it is not meant to support the weight of someone leaning or falling against it. The warning line must be flagged every 6 feet or less with high-visibility material so that workers can easily see the line. The warning line must be not less than 34 inches above the working surface at the lowest sag point and no more than 39 inches above the surface at the high point. The line must be erected around all sides of a roof work area, at least 6 feet from the edge. 15

16 Other points about warning line systems include: Stanchions must not tip over easily they should be able to resist a force of at least 16 pounds after being rigged with the warning line. Workers must be trained to stay out of the unprotected area beyond the warning line. Work that must be done outside the warning line requires another kind of fall arrest system to be put in place. 16

17 A safety monitor system is used only when no other alternative means of fall protection can be used: A competent person is appointed to monitor and warn workers of potential fall hazards while you are working. The monitor must be able to recognize potential fall hazards. The monitor communicates with workers and alerts them both to hazards and to unsafe work practices. He or she must be on the same working or walking surface as the other workers and always be able to see them and be close enough to talk to them. The monitor must have no other duties to perform while acting as safety monitor. The monitor keeps unauthorized workers, materials, and equipment from the area that is being monitored. Finally, all workers in the monitored area must comply with any fall hazard warnings issued by the safety monitor. 17

18 Controlled Access Zones, or CAZs, apply to certain specific types of work, such as overhand bricklaying. CAZs are regulated work areas without conventional fall protection systems. A CAZ is a combination of a warning line system and a safety monitoring system. Access to the CAZ is limited only to qualified employees who are authorized to be there. For example, these may be specialty workers, such as masons. A CAZ does allow work without fall protection systems. Typically, the guardrails have been removed from a leading edge. The CAZ is clearly designated and marked. It must be defined by a control line or other means to restrict access to the area. Control lines should run the entire length of the unprotected edge and should run parallel to it. Control lines are connected on each side to a guardrail system or a wall. The control lines should be set up no closer than 6 feet and no more than 25 feet from the unprotected edge. For work such as overhand bricklaying, the control lines should be 10 to 15 feet from the unprotected edge. 18

19 Hole covers are intended to prevent a number of possible falling hazards. A person could trip, twist an ankle, fall partially into a hole, or drop materials to a lower level. A cover prevents a worker, or a worker s body part, from penetrating a walking or working surface. Covers are required for all holes equal to or greater than 2 inches wide. Covers must be able to support twice the weight of persons or equipment expected to cross over it. For example, a cover located in a roadway or a vehicular aisle must be able to support twice the weight of the largest vehicle likely to be on it. Covers need to be secured to prevent accidental displacement by equipment, employees, or wind. Finally, covers must be color-coded or marked with the word Hole or Cover. 19

20 Preventing objects from falling from elevated work areas is accomplished in a number of different ways. Use screen or panels with guardrail systems to prevent tools or equipment from falling on workers below. Screens and panels should be installed so that they extend from the working surface to the top rail. Store materials at least 4 feet from the edge of open surfaces. Only masonry bricks and mortar may be closer than 4 feet from the edge. Excess material and debris should be kept out of the work area and removed at regular intervals. For roofing work, store materials at least 6 feet away from the roof edge unless guardrails are erected at the edge with screens or panels. Also, materials stacked near the edge should be stable and selfsupporting. Use canopies as a way to protect workers below; canopies must be strong enough to prevent collapse, as well as to prevent penetration by any falling object. Keep areas barricaded where objects are likely to fall; this prevents workers from walking through the area and subjecting themselves to danger. 20

21 Use toeboards as another way to prevent objects from being accidentally kicked over the edge. They should be placed along the edge for a distance sufficient to protect anyone below. They need to be strong enough to withstand a force of at least 50 pounds and be at least 3½ inches high from the working surface. If tools, equipment, or materials are piled higher than the toeboard, paneling or screening should be installed. Keep tools, materials, and debris picked up so that they can t be accidentally kicked over the edge. Never throw objects down to lower levels, even if you think there is no one below. If it is necessary to throw objects to a lower level, the area beneath you should be barricaded to keep people away. Always wear a hard hat if you are working underneath workers on a higher level. 21

22 Do you understand basic fall restraint systems: guardrails, harnesses, controlled access zones, warning lines, hole covers, safety monitoring, or preventing objects from falling? It s time to ask yourself if you understand the material presented so far. It s important for your safety that you understand how to protect yourself against falls and falling objects. 22

23 Now we ll discuss fall arrest systems. Remember, fall arrest systems do not prevent someone from falling but are intended to stop a free fall. One type of fall arrest is a safety net system. These are nets intended to catch falling workers. They should be installed under the working surface, as close to the surface as possible. The net should never be more than 30 feet below the working surface. Safety nets should be inspected regularly at least once a week. Look for signs of wear, damage, and other deterioration. Openings in the net should never be more than 6 inches across. There should be sufficient clearance underneath to prevent you from contacting the surface or structure below if you should fall into the net. Finally, remove items that have fallen into the net, including tools, scraps, and other materials. This is to prevent a worker who falls into the net from being injured. Objects should be removed as quickly as possible or at least before the next work shift begins. 23

24 A personal fall arrest system with a harness is the most effective fall arrest system to protect you from injury. The harness distributes the arresting forces among the structural components of your skeletal system, including your thighs, pelvis, waist, chest, and shoulders. The harness is rated for a maximum of 1,800 pounds of arresting forces. A harness can also be used for positioning a worker or for suspending a worker if necessary for specialized types of work. A body belt is NOT authorized for use as a part of a fall arrest system. Belts can cause damage to the spine or internal organs when used to arrest a fall. However, body belts can still be used as a positioning device. The D-ring on the upper back, shown on the photo, is important for fall arrest. Make sure your anchor point is always above this location to limit the height of the fall. If your anchor point is below your upper back, use a shorter lanyard to limit your fall distance to 6 feet. 24

25 Here are the elements of an effective personal fall arrest system: The system should be set up to have a maximum arresting force of 1,800 pounds. The force of the stop is determined by your body weight and the distance of the fall: the arresting force is equal to your weight times the distance. The more you weigh and the longer your fall distance, the more force it takes to stop a fall. A free fall should be no more than 6 feet; the fall arrest system should be rigged to make sure of this limit. At a 6-foot fall distance, you would need to weigh more than 300 pounds to suffer arresting forces of more than 1,800 pounds. The system also must be rigged to prevent you from contacting a lower level during a free fall. The system must bring you to a complete stop, and limit the distance in which you decelerate to no more than 3 1 / 2 feet. There will be less arresting force if you can decelerate for a few feet rather than come to a sudden stop. Finally, the personal fall arrest system must be designed to withstand twice the potential impact forces of someone falling for a distance of 6 feet. 25

26 Connectors are a critical component of any personal fall arrest system. Connectors, including snaphooks and rings, are used to attach the lanyard to the anchor and the harness. Ensure that the snaphooks properly lock into place by inspecting them regularly. Nonlocking snaphooks are prohibited for fall protection. Note that proper snaphooks are frequently self-locking; they will automatically lock shut after they have been hooked and must be manually unlocked in order to be released. 26

27 Unless snap hooks are the locking type and designed for the following uses: Don t attach them directly to webbing or rope. Don t attach to another snaphook. Don t attach them to a D-ring that has another snaphook or connector attached to it. Don t attach them to horizontal lifelines. Finally, don t attach them to an object that is not compatible in shape or dimension. Doing so might cause the connected object to depress the snaphook keeper and release it accidentally. 27

28 A lanyard, of course, is a key component of a fall arrest system. A lanyard is a flexible line of rope or strap with a connector that connects the harness to an anchor point. It can also be connected to a lifeline or a deceleration device. A lanyard often contains its own deceleration device that is intended to greatly reduce arresting forces. Different lanyards use different means, such as tearing or stretching, to absorb the shock of a sudden stop. Think about what might happen if the lanyard were made of steel cable it would not give or stretch to absorb any of the forces, so all the forces would be absorbed by the worker. By contrast, the deceleration device on the lanyard reduces arresting forces by giving and by preventing you from bouncing. Lanyards should not have any knots, and they should never be wrapped around sharp objects. Note that knots can reduce the strength of a lanyard by up to 50%. 28

29 A lifeline can be part of a fall arrest system, but it is not the same as a lanyard. Lifelines connect the personal fall arrest system that is, the harness and the lanyard to an anchor point if the anchor cannot be reached by a short lanyard. In a sense, the connection between the lanyard and the lifeline becomes the anchor point. The lifeline is not intended to stretch to add to the length of a fall. A lifeline should be designed, installed, and used under the supervision of a qualified person and should not be used as a substitute for a lanyard. The lifeline can hang vertically from one anchor point. The lanyard is connected at the end of the vertical lifeline. The lifeline also can be stretched horizontally between two anchor points. In this case, the lanyard can be connected at any point along the horizontal line. Lifelines are generally ropes or straps made of synthetic fiber. They must be able to withstand 5,000 pounds of force. Lifelines should be protected against being cut or abraded, so they should be kept away from sharp edges. 29

30 A deceleration device is used with a fall arrest system to reduce the forces on your body as the result of a fall. It dissipates a substantial amount of energy in arresting the fall. Rip-stitch, tearing, or stretching lanyards are the most common types of lanyards. The maximum deceleration distance is 3 1 / 2 feet. Remember to account for this distance when checking if your fall location is clear. A rope grab device travels on a lifeline and automatically, by friction, engages the lifeline and locks to arrest the person s fall. This type of device might be used as part of fall protection system for climbing high ladders. Retracting lanyards or lifelines include devices that allow the line to be slowly extracted from or retracted into a drum that is under slight tension when the worker is moving about normally. Fall arrest systems with rope grab devices or retracting devices can be more than 6 feet long, so these types of devices give workers more flexibility. A lanyard is required between these types of devices and the harness if there is no other deceleration device that is part of the system. 30

31 The anchors of a fall arrest system are critically important. A fall arrest system is only as good as its anchor. An anchor is a secure point of attachment for a lanyard, lifeline, or deceleration device. An anchor should be designed to support at least 5,000 pounds per person that is attached to it. Ideally, the anchor point should be located above you. If it is shoulder height or higher, this will reduce the length of the fall and reduce the possibility of swinging and hitting something. Remember, the maximum allowable distance for a free fall is 6 feet. The further the fall, the greater the arresting forces on you. Ask a supervisor if you are unsure about proper anchor points. Keep in mind that you should not anchor to electrical conduits, water lines, or guardrails. There is no point in tying to an anchor at all if it is not strong enough to withstand the arresting forces of a fall. 31

32 Always inspect your personal fall arrest system. It should be inspected before each use. After all, your life may depend on the integrity and condition of the equipment. Check D-rings and snaphooks for any sign of cracking, breaking, or deformation. They each must have a tensile strength of 5,000 pounds. Check the ropes, straps, and tongue buckle for cuts, tears, abrasions, loose stitches, and other defects. Ensure that all moving parts are able to move freely and are operating as designed. Snaphooks should work easily and lock correctly. Ropegrab devices and retracting lifelines should also be working correctly. Remove any defective components that you find. Defective equipment should be tagged Out of Service and sent back to the manufacturer for repair and recertification. 32

33 A rescue plan is another important part of fall protection. The purpose of the rescue plan is to safely, in the shortest time possible, rescue a worker who has fallen. It s important to minimize the time being suspended after a fall because of something called suspension trauma. If suspended in an upright position, blood is pulled down into the lower legs by gravity. Eventually, the flow of blood and oxygen to the brain is reduced. If you were standing on the ground when these flows are reduced, you would faint and become horizontal, which would help get the blood to circulate out of your legs and back to your brain. However, if suspended in an upright position, you will faint and remain vertical, meaning recirculation cannot occur. If you are suspended in a harness: Push your legs against an object because actively using leg muscles will help push blood out of your legs; and Raise your legs if possible. 33

34 Do you understand the information on fall arrest systems? Now it s time to ask yourself if you understand the information presented so far. It is important for your safety that you understand the information on fall arrest systems. 34

35 What s wrong with this picture? This worker is trying to repair a sprinkler head 14 feet above a concrete pad. What are the fall hazards? The main hazard is that she is working close to an unprotected edge. If she were to fall, she would land on concrete 14 feet below. What fall protection systems are missing? For one thing, the platform has no guardrail or toeboard. Also, she is not wearing a harness for fall restraint or fall arrest. 35

36 Now we ll summarize the key points to remember about this training session on fall protection: First, learn to recognize all of the potential fall hazards in your work area, such as working near an unprotected edge. Always remember to use and operate fall protection systems, such as fall restraints and fall arrest systems. These may include guardrails, warning lines, safety monitoring systems, CAZs, safety nets, hole covers, and personal fall arrest systems with harnesses, lanyards, and lifelines. Implement safe work practices, such as keeping your work area clean and free from potential falling objects. Inspect your fall protection systems before each use. Make sure they are safe and will provide the protection you need. Protect others from falling objects by keeping your work area clean and keeping tools and equipment away from unprotected edges and openings. Finally, be prepared to rescue and assist yourself and others in case of a fall. This concludes this training session on Fall Protection in Construction. 36