Overhead electricity lines

Since aerial lifts carry people up, fall hazards come into play. In addition, overhead lines must be avoided. If overhead electrical lines carry 50 kV or less, you must maintain a clearance of at least 10 feet. If the lines carry more than 50kV, clearance must be 10 feet plus 0.4 inches for every extra kV. Depending upon the type of work being performed in the lift, other hazards may be involved. 

Cranes all too often come in contact with overhead electrical lines at work sites. 

Work near underground electricity cables and overhead electric lines has caused many serious and fatal accidents over the years. The precautions to be taken are admirably dealt with in two HSE Guidance Notes on Avoidance of Danger from Overhead Electric Lines and Avoidance of Danger from Buried Electricity Cables . 

Health and Safety Executive, Avoidance of Danger from Overhead Electricity Lines, Guidance Note GS 6, HMSO, London (1977)... 

HSE Guidance Notes, HMSO, London GS 6 Avoidance of danger from overhead electrical lines (1980)... 

GS 6 Avoidance of danger from overhead electrical lines... 

HSE Guidance Note GS6 - Avoidance of danger from overhead electric lines HSE Booklets HSG 144 - Safe use of vehicles on construction sites HSG 151 - Protecting the public - your next move... 

On stretches of electric line, according to Ref. 12, filling tracks without overhead conductors are usually isolated from the rest of the rail network with insulating joints in order to keep the rail currents flowing to the tank installation as... 

Many of the uses listed in Table A are a matter of everyday observation. In nddition we may nole that the electrical conductivity of pure A1 is 63.5% of the omduedvity of an equal whune of pure Cu when the lower density of A1 is considered its conductiviQr is 2.1 times that of Cu on a wt for wt. basis. This, coupled with its corrosion resistance and ready workability makes it an ideal metal for power lines and. indeed, more than 90% of all overhead electrical transmission lines in the USA are A1 alloy. 

Aluminum s low density, wide availability, and corrosion resistance make it ideal for construction and for the aerospace industry. Aluminum is a soft metal, and so it is usually alloyed with copper and silicon for greater strength. Its lightness and good electrical conductivity have also led to its use for overhead power lines, and its negative electrode potential has led to its use in fuel cells. Perhaps one day your automobile will not only be made of aluminum but fueled by it, too. 

The forces released when the tank car skin ruptured were quite impressive. Parts of the car were found 250-300 yards (228-274 meters) away from the skin. The wheels of the car were driven into the ground about 2 feet (61 cm) while the wheels were still on the rails. The skin of the car was essentially flattened, with the impressions of the two rails clearly seen through the skin. The sound of the explosion was heard about 10 miles away. The overhead 138,000-volt electrical lines were severed, and the arcs resulted in two small grass fires. Plants connected to these electrical lines were shut down. There was no fire from the polymerization. In addition to the car that was destroyed, nearby cars were also damaged. Foam-like polymer covered an area about 200 by 50 yards (182 by 46 meters). Because of the precautions we had taken, there were no injuries. 

Common sources of low-level exposure to electromagnetic fields are electric and magnetic powered transport (static fields), overhead power lines, domestic electric appliances (ELF), antitheft electronic devices, or video display units (in very low to low... 

Miscellaneous Cranes.— Wall and jib cranes, whether stationary or of the traveling type, hoists of various kinds and all other varieties of cranes lend themselves to economic selection and analyses as to probable net cost of operation along lines very similar to those followed in the case of overhead electric cranes. A full knowledge of operating requirements is necessary, suitable provisions should be made for possible expansion, and the mistake avoided of assuming too great a mechanical efficiency for the equipment. An intimate knowledge of costs— labor and equipment—and depreciation expenses is also required for even such approximate estimates, if they are to be at all reliable. 

Because of its high electrical conductivity, Al is used in overhead power lines. Its high negative electrode potential has led to its use in fuel cells. 

Electrical entrance package- The entry point of the electrical power including (1) the strike or location where the overhead or underground electrical lines connect to the house, (2) The meter which measures how much power is used and (3) The panel or circuit breaker box (or fuse box ) where the power can be shut off and where overload devices such a fuses or circuit breakers and located. 

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. 

Ask your trainees if they know of anyone injmed by an electric arc accident. Discuss possible scenarios where a worker could be exposed to arc flash (working near overhead power lines, working near exposed electrical equipment). Discuss any company-specific training that yom- employees need to know. 

Electrical (e.g., overhead power lines, power tools and cords, outlets, temporary wiring.)... 

Electrical Safety — Overhead Power Line Safety... 

ELECTRICAL SAFETY — OVERHEAD POWER LINE SAFETY-1... 

J. J. KELLER S CONSTRUCTION TOOLBOX TALKS Electrical Safety — Overhead Power Line Safety... 

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