Roofs ladders

Figure 8.16 (a) Roof ladder. The ridge iron should be large enough to be clear of the ridge tile, (b) Permanent protection installed at valley gutter (the protection should be supported by at least three rafters beneath the roof sheets). 

Suitable means of access, such as roof ladders, crawling boards, scaffolding and staging must be provided. 

Underwriters Laboratories 333 Pfingsten Road Northbrook, Id. 60062 Standards for Safety is ahst of more than 200 standards that provide specifications and requirements for constmetion and performance under test and in actual use of a broad range of electrical apparatus and equipment, including household appHances, fire-extinguishing and fire protection devices and equipment, and many other nongenerady classifiable items, eg, ladders, sweeping compounds, waste cans, and roof jacks for trader coaches. 

FIG. 10-194 Cost ( 30 percent) of field-erected, floating roof tanks, October 2005, includes concrete foundation and typical nozzles, ladders, and platforms. 

Sledge carry/roof walk Pick up a sledgehammer (8 to 10 pounds) and walk with it on a ladder that is suspended above the ground on sawhorses. (This simulates walking along a roof line.)... 

Back channels height is 3 meters its width is also 3 meters. Adopting the bolts which made of steel with thread and the model is q)22 mm x 2000 mm to support the roof The distance between two bolts is 1500 on the vertical, 1100 on the transverse, and they are equipped with mesh reinforcements and ladder beams there is a row of strand anchor cable in the roof, the model of the strand anchor cable is [Pg.48]

Vertical cylinder, API movable roof c/s atmospheric pressure, lifter type, 1.5 m lift, liquid seal, including access holes, relief valves, roof supports, glide slides, spiral staircase, ladder, usual flanged connections excluding foundation and dyking. Field erected cost 700000 for tank volumetric capacity = 4000 m with n = 0.63 for the range 1000-12 000. Factors, pontoon, X 0.85 3 m lift, X 1.3. 

Electric shock occurs when a person becomes part of the electrical circuit, as shown in Fig. 1.30. The level or intensity of the shock will depend upon many factors, such as age, fitness and the circumstances in which the shock is received. The lethal level is approximately 50 mA, above which muscles contract, the heart flutters and breathing stops. A shock above the 50 mA level is therefore fatal unless the person is quickly separated from the supply. Below 50mA only an unpleasant tingling sensation may be experienced or you may be thrown across a room or fall from a roof or ladder, but the resulting fall may lead to serious injury. 

National Institute for Occupational Safety and Health (NIOSH) records indicate that between 1992 and 2005 falls to lower level, electrocution, highway incidents, and being struck by an object were the leading causes of death in construction. One-third of the fall-related deaths were falls from a roof, 18 percent were falls from scaffolding, and 16 percent were falls from ladders. Electrocutions accounted for 9 percent of the deaths in construction in 2005. The main cause of electrocution for electrical workers was direct contact with energized equipment and wiring, while over half the electrocutions of non-electrical workers were caused by contact with overhead power lines with objects including ladders, poles, and cranes. 

Ladders reaching to a platform or roof must rise at least 1 metre above the landing place. 

Accessing the roof with ladders that did not extend 3 feet above the landing,... 

Accessing the roof with a ladder made longer by using a bungee cord to attach a second ladder to it, and... 

Jerry was told by his supervisor to find a ladder to use to safely reach to the top of a second story roof. Jerry checked out the height of the roof (about 15 feet) and figured he needed to find a ladder about 20 feet long. Away he goes to find a ladder. He really wants to impress his supervisor and quickly finds a 20-foot ladder. 

Jerry hauls the ladder back and sets it up. After he is done he notices that the side rails were just barely over the edge of the roof. Oh well, he thought, it should be OK. ... 

Should Jerry have made a more accurate assessment of the ladder length need to safely reach the roof top Yes, he should have realized that if the height was 15 feet, a 20-foot ladder would not be enough to provide a 4-to-l climbing ratio. 

Should Jerry have made a more accurate assessment of the ladder length need to safely reach the roof top ... 

OSHA cited a Massachusetts roofing contractor for 16 alleged violations of safety and health standards. The company faces a total of 79,000 in proposed fines for ladder, fall, scaffold, and other hazards identified at a residential construction site. 

OSHA s inspection found employees working on a two-story roof without fall protection and accessing the roof and scaffolding on ladders that did not extend at least three feet above the upper landing surface. As a result, OSHA issued the company two willful citations, carrying 56,000 in proposed fines, for those conditions. OSHA defines a willful violation as one committed with plain indifference to or intentional disregard for employee safety and health. 

Special Scaffolds There are many kinds of specialty scaffolds. Ladder jacks attach to straight or extension ladders. Two ladders with ladder jacks will support planks between them. Users nail roofing brackets to roofs with steep slopes or suspend them with ropes and proper anchors. The brackets support planks between them that workers stand on. After roofing is complete, users remove the planks and brackets. 

Only stairs, passageways, and ladders approved for use in the demolition process are to be used in these buildings. These stairs or ladders are to be periodically inspected. Any stairwell being used in a multilevel building must be properly illuminated and have protective roof coverings where necessary. 

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