Document DvKnbV552Doa9xayGQ2m0XZwd

Wednesday, December 28, 1960 FEDERAL REGISTER 13815 it and the pressure reducer. There shall equal to eight diameters of the cable, or 50--204.139 Protection to oilier em be no means of cutting off or bypassing when the wires on the crown of the ployees. this safety valve. Inspection and ade quate maintenance of the vessel. Includ ing regular testing of the safety valve, are mandatory. 50-204.122 Unfired pressure vessels. (a) Air receivers shall be so installed that all drains, handholes, and manholes therein are easily accessible. <b> Air receivers shall be supported with sufficient clearance to permit a com plete external inspection and to avoid corrosion of external surfaces. (c) Under no circumstances shall air receivers be burled underground or lo cated In an inaccessible place. (d) The receiver shall be located as close to the compressor or aftercooler as Is possible to keep the discharge short (e) The receiver shall be located in a cool place to facilitate the condensation of moisture and oil vapors, strand are worn down to less than 60 percent of their original diameter. (d> Crane hoist cable shall be lu bricated and inspected at frequent Intervals. Ventilation and Protection in Welding and Cutting 50--204.135 -Welding nnd culling in cun lined pace*. For the purpose of this section a con fined space shall mean: (a) A space of less than 10,000 cubic feet per welder, or (b) A space having an overhead height of less than 18 feet, or (o> A space In which there are struc tural barriers to the extent that they significantly obstruct cross ventilation. 50-204.136 Vcntilutiun in confined paces. In all cases employees In the Immedi ate vicinity of welding operations shall be protected in accordance with sections 60-204.269 and 50-204.298. 8 50--204.140 liien-gus iiictid-im.- wdil. mg- Since the inert-gas metal-aro welding process involves the production of ultra violet radiation of Intensities five to thirty times that produced during shielded metal-aro welding, the decom position of chlorinated solvents by ultra violet rays, and the liberation of toxic fumes and gases, employees shall not be permitted to engage in, or be exposed to the process unless: (a) The use of chlorinated solvents is kept at least 200 feet from the exposed arc; surfaces prepared with chlorinated solvents are thoroughly dry before welding Is permitted on such surface. Toots and Equipment 30-204.127 Mainlenanrc. All welding and cutting operations car (b) Shaded goggles with side shields ried on in confined spaces shall be ade are worn by helpers and others in the quately mechanically ventilated to pre area not protected from the arc by Each employer shall be responsible for vent the accumulation of toxic gases or screening. the safe condition of the tools used by his possible oxygen deficiency or air sup (c) Protective clothing Is worn by employees, whether furnished by him or plied respirators approved by the U.S. welders and others within the area ex by them, and be sure that such tools are Bureau of Mines shall be provided to the posed to radiation so chat the skin is suited by safe design and construction welder and all other personnel in the covered completely to prevent bums and for the work to be done. immediate vicinity. other damage by ultraviolet rays; shirts 50-204.128 Portable electric power took. <a) Electric power tools showing worn. deteriorated or inadequate insulation, split or chipped plugs, worn or bent plugs, terminals, defective switch, shall be repaired. (b) Portable electric power tools shall be effectively grounded to maintali at all times an effective ground on the noncurrent carrying parts of the tools. 50-204.129 Portable pneumatic took. (a) The operating trigger on portable hand-operated pneumatic equipment shall be so located as to minimize the 50--204.137 Mechanical ventilation. Mechanical ventilation shall consist of either general ventilation systems or lo cal exhaust systems. <a> General ventilation shall be at the minimum rate of 2.000 cubic feet per minute per welder. (b) Local exhaust shall consist of freely movable hoods Intended to be placed by the welder as near as prac ticable to the work being welded and pro vided with a rate of air flow sufficient to maintain a velocity In the direction of the hood of 100 linear feet per minute in the zone of welding when the hood is at its most remote distance from the point worn are dark in color to reduce reflec tion to tho face from underneath the helmet; exposed cotton clothing Is cov ered since It disintegrates rapidly when exposed to high intensities of ultraviolet rays; welding helmets and hand shields are free of leaks and openings, and free of highly reflective surfaces. (d > Local exhaust ventilation or sup plied air respirators are provided In all cases when doing inert-gas metal-arc welding of stainless steel to protect against dangerous concentrations of nitrogen dioxide. 50--204.141 Central welding and cut ting. possibility of accidental operation and of voiding. Welding and cutting not Involving shall be arranged to close the air inlet valve automatically when the pressure of the operator's hand Is removed. 50-204.138 Welding utid culling in volving inclnlt of toxic significance. conditions or materials described in sec tions 60-204.135 and 60-204.138 may normally be done without special pre (b) A tool retainer shall be installed fa) Welding and cutting Involving the cautions, but where, because of unusual on each piece of pneumatlo equipment following metals whether or not In con physical or atmospheric conditions, a which, without such a retainer, may fined spaces or In other enclosed spaces harmful accumulation of contaminants eject the tool. shall be done In accordance with the pro would exist, mechanical ventilation or (c> Mo tool change or work other than visions of sections 204.136 and 204.137. suitable respiratory protective equipment regular operations shall be made or done U) Zinc-bcarlng base of filler metals shall be provided. on any piece of portable hand-operated pneumatic equipment unless the stop or metals coated with zinc-bearing ma terials. Electrical Installation and Equipment valve in the air line supplying that equip (2) Lead base metals. 50-201.1-18 I'.lei-trirul InMu lintion mill ment is closed. (3) Cadmium-bearing filler materials. equipment. 50-201.130 Cubic.*, rope*, ami chains. (a) Chains, ropes, cables, hooks, rings, slings, and other devices and accessories used for hoisting and lifting shall not be subjected to greater workinc loads than recommended by their manufacturers. They shall be frequently inspected and shall be renewed when JnpectJon reveals unsafe conditions. (b) Welding or cutting involving the following metals in confined spaces shall be done using local exhaust ventilation or air-line respirators approved by the U.3. Bureau of Mines. < 1) Metals containing lead, other than as an impurity, or metals coated with lead-bearing materials, including paint. (2) Cadmium-bearing or cadmium- coated base metals. Electrical conductors and equipment installed within or on buildings and other premises and the conductors that connect the installation to a supply of electricity and other outside conductors adjacent to the premises shall conform to the minimum requirements of the Na tional Electrical Code, 1959 Edition, National Fire Protection Association. <h) Bolts or nails shall not be used (3> Metals coated with mercury-bear Mechanical Power Transmission to connect, splice, or shorten chains. ing metals, Including paint. Apparatus Knots shall not be tied in the chain. to) A hoist cable shall be considered (4) Beryllium-containing base or filler metals. Because of its high toxicity, 50-201.15.7 Flywheel*. unsafe and shall be replaced when upon work involving beryllium shall be done Flywheels located so that any part is inspection 10 percent or more of the total with both local exhaust ventilation and 7 feet or less above floor or platform shall number of wires are broken in a length air-Unc respirators. be guarded in one of the following ways: