Work at height safety

Fall hazard means a circumstance that exposes a worker in a workplace to a risk of a fall that is reasonably likely to cause injury to the worker or other person.
Assessing risks from working at height.
Common Fall Hazards at construction site.
Common Scaffold Hazards.
PERSONAL FALL PROTECTION.
Travel-Restraint Systems.
Fall-Arrest Systems.
Lifelines.
Scaffolding, also called scaffold or staging, is a temporary structure used to support a work crew and materials to aid in the construction, maintenance and repair of buildings, bridges and all other man made structures.

1. Work at Height

2. Work at height Fall from height: ( i ) Material Fall (ii) Fall of person 56% of accidents are reported due to fall from height and highest percentage of accidents in construction. It is most common activities in construction. Negligence and leniency are one of major causes of accidents. Competency in this areas is limited.

3. Definitions Fall - a fall by a person from one level to another. Falling object – an unsecured object (e.g. a spanner) falling from height can cause serious injuries if controls are not implemented to eliminate or minimise the associated risks. Fall hazard means a circumstance that exposes a worker in a workplace to a risk of a fall that is reasonably likely to cause injury to the worker or other person.

4. What is a fall hazard? A fall hazard is an anything that exposes a worker or another person to the risk of a fall that may injure them.

5. Fall Hazards Fall hazards can be found on every construction site: Building structures Exterior construction areas Scaffolds Stairs Ladders

6. Situations that pose fall hazards include when a worker is: In or on plant or a structure that is at an elevated level (e.g. a covered walkway). In or on plant that is being used to gain access to an elevated level (e.g. a ladder). Near an opening through which a person could fall (e.g. an open pit). Near an edge over which a person could fall (e.g. standing near the edge of a roof, standing under scaffold).

7. On or near a surface through which a person could fall (e.g. a fragile roof or skylight). On or near a slippery, sloping or unstable surface (e.g. a steep embankment).

8. The risks of working at height Main falling hazards are due to: i . Fall of objects ii. Fall of person it may results due to inadequate edge protection, or material storage are inadequately secured. There are many jobs leads to fall hazards. E.g. painters, decorators and window cleaners and those who undertake one-off jobs without proper training, planning or equipment.

9. Assessing risks from working at height If work at height cannot be avoided, a risk assessment should be carried out before any work at height is undertaken. The assessment should highlight the measures that must be taken to ensure people are not at risk of falling from height. The risks associated with working at height must be assessed. There are few steps recommended ---

10. Assessing risks from working at height Work assessment Activity assessment Hazard Assessment Who are going to exposed Number of person involved Control measures implemented Risk Level Minimization of risk Final assessment of risk Decide : Go head or stop the work.

11. Common Fall Hazards at construction site Common Fall hazards at construction site due to: Improperly stacked poorly secured material Inadequate edge protection Inadequate mean of access Poorly design of structure Designer recommendation not adequately implemented Unstable structure/ supports etc. Base support not on firm ground Fall arrest system inadequate Improper material / man carriage Work station condition Slip/ trip/ hit Inadequate resources Quality of resources Manpower selection Training & education ------------ & so on…

12. Common Scaffold Hazards Getting struck by falling tools or debris Electrocution Scaffold collapse Defective wood planks and inadequate planking overhang. Uneven and uncompact ground Unsafe access to scaffold. Cross bracing not adequate. Inadequate footings. Bridging of scaffolds. High winds and skiddy surface due to rain Nature of electrical, fall, and falling object hazards No guardrails on scaffolds.

13. PERSONAL FALL PROTECTION A worker at risk of falling certain distances must be protected by guardrails or, if guardrails are not practical, by a travel restraint system, fall-restricting system, fall-arrest system, or safety net.

14. Travel-Restraint Systems A travel-restraint system lets a worker travel just far enough to reach the edge but not far enough to fall over.

15. Travel-Restraint Systems The basic travel-restraint system consists of • Approved full body harness • Lanyard • Lifeline • Rope grab to attach harness or lanyard to lifeline • Adequate anchorage (capable of supporting a static load of 15 KN with a recommended safety factor of at least 2)

16. Fall-Arrest Systems Where workers cannot be protected from falls by guardrails or travel restraint, they must be protected by at least one of the following methods: - fall-restricting system - safety net - fall-arrest system. In the event of a fall, these systems must keep a worker from hitting the ground, the next level below, or any other objects below.

17. Lifelines There are three basic types of lifelines: 1) vertical 2) horizontal 3) retractable. All lifelines must be inspected daily to ensure that they are - free of cuts, burns, frayed strands, abrasions, and other defects or signs of damage - free of discolouration and brittleness indicating heat or chemical exposure.

18. Lifelines 1) Vertical Lifelines Vertical lifelines must comply with the current edition of the applicable standard and the following minimum requirements: - Only one person at a time may use a vertical lifeline. - A vertical lifeline must reach the ground or a level above ground where the worker can safely exit. - A vertical lifeline must have a positive stop to prevent the rope grab from running off the end of the lifeline.

19. Lifelines

20. Lifelines 2) Horizontal Lifelines The following requirements apply to any horizontal lifeline system: - The system must be designed by a professional engineer according to good engineering practice. - The design can be a standard design or specifically engineered for the site.

21. Lifelines

22. 3) Retractable Lifelines In general, retractable lifelines - are usually designed to be anchored above the worker - employ a locking mechanism that lets line unwind off the drum under the slight tension caused by a user’s normal movements - automatically retract when tension is removed, thereby preventing slack in the line - lock up when a quick movement, such as that caused by a fall, is applied - are designed to minimize fall distance and the forces exerted on a worker’s body by fall arrest.

23. INTRODUCTION Scaffolding , also called  scaffold  or  staging , is a temporary structure used to support a work crew and materials to aid in the construction, maintenance and repair of buildings, bridges and all other man made structures. Scaffolding is also used in adapted forms for formwork and shoring, grandstand seating, concert stages, access/viewing towers, exhibition stands, ski ramps, half pipes and art projects.

24. INTRODUCTION More than half of scaffold accidents in construction areas are falls. Several fatalities are also related to scaffolds each year. The number and severity of injuries involved make scaffold accidents one of the more serious safety problems in construction.

25. Problem Areas The main problem areas are • Erecting and dismantling scaffolds • Climbing up and down scaffolds • Planks sliding off or breaking • Improper loading or overloading • Platforms not fully planked or “decked” • Platforms without guardrails • Failure to install all required components such as base plates, connections, and braces • Moving rolling scaffolds in the vicinity of overhead electrical wires • Moving rolling scaffolds with workers on the platform.

26. Types of scaffolds Standard Tubular Frame scaffolds Standard Walk-through Frame scaffolds Rolling scaffolds Fold-up scaffold Frames Adjustable scaffolds Tube-and-Clamp scaffolds Systems scaffolds Mast-Climbing Work Platforms Crank-up or Tower scaffolds

27. Standard Tubular Frame scaffolds This is the most frequently used scaffold in construction. Historically it has been made of steel tubing, but aluminum is gaining popularity. The scaffold is manufactured in various configurations and spans. On some systems, ladder rungs are built into the end frames .

28. Standard Walk-through Frame scaffolds This is a variation of the standard tubular frame scaffold. Although primarily designed to accommodate pedestrian traffic at the ground or street level, the walk-through scaffold is frequently used by the masonry trade to provide greater height per tier and easier distribution of materials on platforms at intermediate levels.

29. Standard Walk-through Frame scaffolds (cont’d) Although primarily designed to accommodate pedestrian traffic at the ground or street level, the walk-through scaffold is frequently used by the masonry trade to provide greater height per tier and easier distribution of materials on platforms at intermediate levels.

30. Rolling scaffolds Rolling scaffolds are best suited where short-duration work must be carried out at multiple locations. They are used mainly by mechanical and electrical trades. There are two main types of rolling scaffold. Castor Type. Farm Wagon Type .

31. Castor Type This type of scaffold is best suited for work on smooth floors and is typically used inside buildings. All castors should be equipped with braking devices. This kind of scaffold should be erected so that its height-to-width ratio is no greater than 3 to 1. This limits the height of platforms with standard outrigger stabilizers and single span towers to approximately 9 metres (30 feet).

32. Castor Type

33. Farm Wagon Type Scaffolds erected on farm wagons or other devices with pneumatic tires are frequently used for installing sheet metal siding and similar materials on industrial buildings. For safe, effective use, the area around the building should be well compacted, relatively smooth and level. This type of scaffold must also have outrigger beams with levelling devices. It is subject to the 3-to-1 height-to-width ratio and is impractical for heights greater than 7.5 metres (25 feet). The scaffold should always be resting on the outriggers while workers are aboard. It should never be used as a work platform while it is “on rubber.”

34. Farm Wagon Type

35. Fold-up scaffold Frames Fold-up scaffold frames are frequently used by trades such as electricians, painters, and suspended ceiling erectors. Widths range from dimensions that will pass through a 750-mm (30-inch) opening to the standard width of about 1.5 metres (5 feet). Frequently made of aluminum, this type of scaffold is easily and quickly transported, erected, and moved about construction sites and from job to job. It should be used only on a smooth, hard surface.

36. Fold-up scaffold Frames

37. Adjustable scaffolds Uses similar to the fold-up model. Although it is not so easily erected, the system is light and very easily adjusted for height. It breaks down into a minimum of components readily transported from job to job. These devices should also be used only on smooth, hard surfaces. They are not intended to carry heavy loads.

38. Adjustable scaffolds

39. Tube-and-Clamp scaffolds Tube-and-clamp scaffolds are frequently used where obstructions or non-rectangular structures are encountered. The scaffolds are infinitely adjustable in height and width. They can also be used for irregular and circular vertical configurations. Tube-and-clamp scaffolds above 10 metres (33 feet) must be designed by a professional engineer.

40. Tube-and-Clamp scaffolds

41. Systems scaffolds European scaffold systems have become very popular in applications that were traditionally suited to tube-and clamp. Although they are not as adjustable as tube-and clamp scaffolds, they can be applied to a wide variety of non-rectangular, circular, or dome-shaped structures. As with tube-and clamp scaffolds, personnel carrying out the erection should be experienced with that type of system and a sketch or drawing of the scaffold to be erected is recommended for each application. Systems scaffolds above 10 metres (33 feet) in height must be designed by a professional engineer.

42. Systems scaffolds

43. Mast-Climbing Work Platforms They are best suited for medium to high-rise projects, and are used also by siding installers, window installers, dry wallers , and other trades. For low to medium height projects they can be free standing, depending on ground conditions and manufacturers’ instructions. For high rise applications they can be tied to the structure at regular intervals as set out by the manufacturer. Mast-climbing work platforms can be used as a single tower or as multiple towers braced together. The platform climbs the mast, normally powered by an electric or gas engine

44. Mast-Climbing Work Platforms

45. Crank-up or Tower scaffolds They consist of towers, bases, and platforms that can be lifted by winches. The working platform is located 600 to 900 mm (2 to 3 feet) below the material platform, which is in an ergonomically good position for the worker. The entire scaffold can be raised easily, allowing the worker a comfortable working height. Crews must be trained to erect, use, dismantle, and maintain tower scaffolding safely and efficiently.

46. Crank-up or Tower scaffolds Manufacturers’ instructions must be followed at all times. Tower scaffolds must be tied to the structure according to manufacturer’s instructions.

47. Scaffold components Tubular Frame scaffolds: There are many tubular frame scaffold components available. Some components are necessary in almost all situations; others are optional depending on use and manufacturers’ instructions. In addition to scaffold end frames, the minimum components required are – base plates or castors – mudsills – adjustable screw jacks – vertical braces on both sides of frames unless

48. Scaffold components • frames are designed with “non-pinned” joints • additional bracing is provided by a designed system using tube-and-clamp accessories – horizontal braces on every third tier of frames – platform materials to fully deck in the intended working level – guardrails complete with toeboards – guardrail posts where working platforms will be at the top level – ladders or stairs for access – intermediate platforms where required—not more than 9 metres (30 feet) apart and adjacent to vertical ladders.

49. Frame scaffold components

50. Frame scaffold components

51. Scaffold components Tube-and-Clamp scaffolds and systems scaffolds Platforms Platforms for frame scaffolds are normally either aluminum/plywood platforms or wood planks. Planks normally come in 8-foot or 16-foot lengths to cover one or two 7-foot bays with adequate overhang.

52. Scaffold components Outrigger/side brackets The use of outrigger brackets also known as side brackets is very popular in the masonry industry. They are attached to the inside of the frame and accommodate a platform approximately 20" (two planks) wide. They provide a work platform for the mason at an ergonomically convenient location, lower than the material platform. Intended as a work platform only, they are not to be used for material storage.

53. Scaffold components Ladders A major problem with ladders built into the frame is that planks sometimes stick out so far that it’s difficult to get from the ladder to the platform. This situation results in many injuries but can be overcome in one of three ways: • Use manufactured platform components which do not project beyond the support • Use a portable ladder where platform elevations are less than 9 metres (30 feet) in height. • Use a stand-off vertical ladder with a cage if the scaffold is above 3 metres (10 feet).

54. Scaffold components Ladder rails should extend at least 900 mm (3 feet) above the platform level to facilitate getting on and off. Injuries are often connected with stepping on and stepping off the ladder at the platform level.

55. Scaffold components Guardrails Failing to use guardrails is one of the main reasons for falls from scaffold platforms. Manufacturers of frame scaffolds have guardrail components which can be attached to the scaffold frames. These have posts that sit directly onto the connector pins and to which the rails are attached using wing nuts.

56. Scaffold components A guardrail should consist of: • a top rail about 1 metre (40 inches) above the platform • a mid-rail about halfway between the platform and the top rail • a toeboard at least 89 mm (31/2") high at the platform level if made from wood, and • posts no more than 2.4 metres (8 feet) apart if made from wood. Guardrail posts can be farther apart if the materials used are adequate to support the loads specified.

57. Scaffold components

58. Scaffold components

59. Erecting and dismantling scaffolds

60. Erecting and dismantling scaffolds Inspection Scaffold materials should be inspected before use for • damage to structural components • damage to hooks on manufactured platforms • splits, knots, and dry rot in planks • delamination in laminated veneer lumber planks • presence of all necessary components for the job • compatibility of components.

61. Scaffold stability Tie-in Requirements Scaffolds which exceed the 3-to-1 rule of height to least lateral dimension must be tied in to a building or structure. Tie-ins should be applied at every third frame vertically second frame horizontally for tubular frame scaffolds. Tie-ins for tube-and-clamp scaffolds should be applied at every second node vertically and every third standard horizontally. These tie-ins must be capable of sustaining lateral loads in both tension (pull) and compression (push).

62. Scaffold stability

63. Training Selecting the type of scaffold to use is as important as tool selection. An ongoing program that trains personnel in selection and use of scaffolding is imperative to reducing accidents in the work place. If you need more detailed information, consult the references and manufacturer’s recommendations.

64. Training (cont’d) Employees must receive training from qualified person that covers: Nature of hazards, electrical, falls, and falling items Use of scaffold / handling Maximum intended load and load carrying capabilities of scaffold Procedures for setup, dismantling or moving the system

65. Retraining When the employer has reason to believe an employee lacks the skill or understanding needed for safe work involving scaffolds, retraining shall be performed until proficiency is established. Retraining is also required when: Additional or new hazards exists Changes occur in the type of scaffold and fall protection exist Where there are inadequacies in an employee’s work

66. Ladders The frequent use of ladders at home and on construction sites tends to dull awareness of the dangers involved in their use. Although there are varieties of ladders, many of the same requirements and safe work practices apply. When using ladders for such use, make sure they are a minimum Type I (250 lb. rating) or greater.

67. Ladders The following are major causes of accidents. — Ladders are not held, tied off, or otherwise secured. — Slippery surfaces and unfavourable weather conditions cause workers to lose footing on rungs or steps. — Workers fail to grip ladders adequately when climbing up or down. — Workers take unsafe positions on ladders (such as leaning out too far). — Placement on poor footing or at improper angles causes ladders to slide. — Ladders are defective. — High winds cause ladders to topple. —Near electrical lines, ladders are carelessly handled or improperly positioned. — Ladder stabilizers are not used where appropriate.

68. Types of Ladders The many types of ladders used on construction sites range from metal ladders permanently mounted on equipment to job-built wooden ladders. Portable Ladders Step, Trestle and Platform Ladders Fixed Ladders Special Purpose Ladders Job-Built Wooden Ladders

69. Types of Ladders Portable Ladders All portable ladders must have non-slip feet or be set up so that the feet will not slip. Portable ladders are available in various grades: light duty or grade 3; medium duty or grade 2; heavy duty or grade1

70. Types of Ladders Step, Trestle and Platform Ladders Apart from the standards of sound construction and reliable service that should apply to all ladders used on site, the primary consideration with these ladders is that they have strong spreader arms which lock securely in the open position.

71. Types of Ladders Fixed Ladders Steel ladders permanently fixed to structures such as stacks and silos are designed for service after construction is complete but are often used by work crews during construction.

72. Types of Ladders Special Purpose Ladders These ladders should be used in accordance with manufacturers' directions and only for the special applications intended.

73. Types of Ladders Job-Built Wooden Ladders Job-built ladders should be constructed according to good structural carpentry practice. The wood should be straight-grained and free of loose knots, sharp edges, splinters, and shakes. Rungs should be clear, straight-grained, and free of knots. Job-built ladders must be placed on a firm footing and be securely fastened in position.

74. Types of Ladders Job-Built Wooden Ladders

75. SUPERVISION AND USE The Supervisor's Task Ladder injuries can be significantly reduced by control of usage and improved site management. This requires that supervisory personnel — train workers to maintain and use ladders properly — evaluate the access requirements of a specific work assignment — choose the best means of access for the job.

76. SUPERVISION AND USE Proper Use of Ladders More than 80 percent of ladder accidents are related to improper use or application of the equipment. Supervisors must control the application of equipment to particular situations. But personnel using the equipment must also be trained to use it. Training should include the following precautions. — Check the ladder for defects at the start of a shift, after it has been used in another location by other workers, or after it has been left in one location for a lengthy period of time.

77. The following are suggested safe work practices when using portable ladders: Keep ladders free of oil, grease and other slipping hazards; Use ladders only for the purpose for which they were designed; Do not load ladders beyond the maximum intended load for which they were built;

78. Do not use the top or top step of a stepladder as a step; Do not climb the cross bracing on the rear section of stepladders unless the ladder is designed and provided with steps for climbing on both sections;.

79. Secure or barricade ladders when using them in passageways, doorways or driveways where they can be displaced by work-place activities or traffic; Keep the area around the top and bottom of the ladder clear; Do not move, shift or extend ladders while occupied;

80. Use ladders only for the purpose for which they were designed; Only use ladders on stable and level surfaces to prevent accidental movement;

81. Never straddle or sit on top of a step ladder.

82. When ascending or descending a ladder, face the ladder; Use at least one hand to grasp the ladder when moving up or down it; A worker on the ladder must not carry any object or load that could cause him or her to lose balance and fall;

83. INSPECTION AND MAINTENANCE Regular inspection and maintenance will increase the useful life of ladders and reduce the number of accidents. Repairs should only be carried out by someone competent and familiar with this kind of work. Ladders found to be defective should be taken out of service and either tagged for repair or scrapped. Once tagged, the ladder must not be used until repaired. Ideally, the tag should only be removed by the person who took the ladder out of service initially. The tag should be printed in big bold letters with the words “DANGER – DO NOT USE”.

84. Training Train each employee to recognize hazards in the use of ladders, such as: • Fall hazards in the work area; • The procedures for erecting, maintaining and disassembling fall-protection systems; • Their proper use and placement; • Their maximum intended loads; Retrain employees as necessary to maintain their understanding and knowledge of safe ladder use.