01 welding and cutting safety

7/29/2019 01 Welding and Cutting Safety

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WELDING AND CUTTING SAFETY




• Safe procedures for safe welding and cutting areextensive because the many hazards involved.• Common hazards include handling compressedgases and exposure to electricity, fumes, gases,noise, radiation, fire and explosions. Thoroughand effective training of workers involved in weldingand cutting is critical to ensure the safe use of equipment and processes, along with procedures

used to control hazardous conditions.• General housekeeping also is important in preventing firesand avoiding injuries, such as a welder trippingover debris or gas hoses due to restricted vision while wearing eye protection.




• Compressed gases• The most frequent OSHA citations related to welding involvethe misuse, careless handling and improper storage of compressed gas cylinders.• Compressed gas cylinders are difficult to handle because Of their size and weight, and the additional hazards due to theexposed valves and gas contents under pressure.• If moving cylinders a short distance, you can tip them and

roll them on the bottom edge. Do not drag the cylindersalong the floor.• Cylinders are best moved with a suitable hand truck. Hoist

cylinders by securing a cradle sling board, pallet or specialcarrier included for this purpose.




• Do not hoist cylinders by use of an electromagnetor choker sling.•

Always store and use cylinders in the upright positionand secure them against falling.• If the cylinders are not labeled, do not use the contents

and return them to the supplier.• Valve protection caps are used to protect the cylinder

valves and the safety devices. Caps should always be inplace except when the cylinders are in use.

• Separate stored oxygen cylinders from fuel-gas cylindersor combustible materials by a minimum distance of 20feet or by a noncombustible barrier at least 5 feet highhaving a fire-resistance rating of at least one-half hour




• Always use a pressure-reducing device when withdrawing gas from gas cylinders used for welding

and cutting operations.• Inspect connection nuts and fittings before each useto detect faulty seats. Faulty seats may allow leakageonce the regulator is attached to the cylinder valves orhoses.

• Before connecting a regulator to a cylinder valve, wipe the valve outlet with a clean cloth free of oil orlint. Then crack the valve by opening the valvemomentarily and closing immediately




• This clears the valve of dust or dirt that mightotherwise enter the regulator. Mark USE NOOIL on gauges used for oxygen service and drainoxygen before attaching to the cylinder.

• Always open oxygen cylinder valves slowly.

• Do not use acetylene at a pressure in excess of 15psig. At about 25 psig acetylene becomesunstable and doesn’t need a spark or flame toexplode.




• Distinguish fuel gas and oxygen hoses from eachother.

• Generally recognized colors are red for fuel gas hose,green for oxygen hose and black for inert gas and airhose.

• Do not interchange the oxygen and fuel gashoses.• You can tape together parallel lengths of oxygen and fuel

gas hose for convenience and to prevent tangling, but notmore than 4 inches in each 12 inches shall be cover with

tape.• Repair or replace hoses showing leaks, burns, wornplaces or other defect.




• Clean torch tip openings that become clogged

with suitable cleaning wires, drills or other devices

designed for such purpose.

• Inspect torches prior to their use for leakingshutoff valves, hose couplings and tip

connections.• Use friction lighters or other approved devices to

light torches, and not matches or hot work.




• Welding produces molten metal, sparks, slag and hot work surfaces.

• Workers should wear protective clothing made of suitablematerials, which provides sufficient coverage to minimize skin

burns caused by sparks, spatter or radiation.• Keep sleeves and collars buttoned, and eliminate pockets from

the front of clothing to prevent sparks from lodging in rolled-upsleeves, pockets or cuffs of overalls or pants.

• All welders and cutters must wear protective flame-resistantgloves.

• Use gloves with insulated linings to protect from exposure tohigh radiant energy.• Employees can use leather or flame-resistant aprons to protect• the front of the body against sparks and radiant energy.• Flame-resistant leggings are available to provide additional

protection to the legs




• When welding or cutting overhead, wear cape

sleeves or shoulder covers with bibs made of leather or other flame-resistant clothing




• Keep clothing free of grease and oil, and don’t carry combustible materials in pockets.

• The equipment and the processes used in weldingand cutting generate noise.• Engine-driven generators can emit high noise levels,as do some high-frequency and induction welding

processes, such as air carbon arc and plasma arccutting. If at all possible, control the noise at thesource. If this is not possible, use personal protectivedevices, such as earmuffs or earplugs




• You must provide adequate ventilation for all

welding, cutting and brazing operations.

• The ventilation must be capable of keepingexposures to hazardous concentrations of airborne contaminants maintained below levels

specified.




• If the airborne contaminants cannot be effectively controlled through natural or mechanical

ventilation, workers must wear respirators• Whenever the use of respirators is necessary,

implement a program to establish the properselection, fit and use of respirators.

• Train welders and cutters to avoid breathing thefume plume directly.• You can do this by work positioning the head or by

ventilation, which directs the plume away from theface.




• Another significant hazard of welding and

cutting operations is the possibility of eye injuries.

• Ultraviolet radiation is generated during these

operations. When the eyes are exposed toexcessive ultraviolet radiation, they may develop

sharp pains and become red and irritated




• Employees will wear proper eye and face protection thatcomplies with the standards and the law of the land for

Practice for Occupational and Educational Eye and Face

Protection.• Employees will wear welding helmets with filter lens, which protect the face, forehead, neck and ears from radiantenergy from the arc and from weld spatter.• Select the filter lens based on the type of welding process being performed, electrode size and arc current.

• Wear safety glasses or goggles to protect against slagchips, grinding fragments, wire wheel bristles and similarhazards.• Welding helmets will not provide adequate protectionagainst severe impact, such as fragmenting grinding wheelsor abrasive discs.




• The welder can avoid electrical shock.Therefore, it is essential that you

thoroughly train him or her on how toavoid it.

• Severity of shock is determined by the

path, duration and amount of currentflowing through the body, which isdependent upon voltage and contactresistance of the area of skin involved.




• Faulty installations, improper grounding

and incorrect operation and maintenanceof equipment are all sources of danger.

• Ground all electrical equipment and the

Work piece




• The work lead is not a ground lead and is usedonly to complete the welding circuit.• Use the correct cable size because overloading will

cause cable failure and result in possible shock or firehazard.

• When electrode holders are left unattended, removethe electrodes and the holders placed or protected so

they cannot make electrical contact with workers orconducting objects.

• Do not dip hot electrode holders in water becausethis may expose the welder or cutter to electric shock.




• Disconnect or de-energize a weldingcircuit

while charging or adjusting the electrode,torch or gun or to avoid electrical shock.

• Inspect welding cable regularly since welding cable is subject to severe abuse asit is dragged over work under constructionand across sharp corners.




• Fire protection

• Welding and cutting should preferably be

done in specially designated areas designedand constructed to minimize fire risk.

• Sparks start many fires, which can travel

horizontally up to 35 feet from their sourceand fall much greater distances.

• Sparks can pass through or lodge in cracks,

holes and other small openings in floors and

walls.




• Material most commonly ignited are

combustible floors, roofs, partitions and buildingcontents.

• This includes trash, wood, paper, textiles,

plastics, chemicals, and flammable liquids and

gases.• Outdoors, the most common combustibles are

dry grass and brush




• When you cannot move work to a designated safelocation, remove all movable nearby fire hazards.

• If the work and fire hazards are immovable, use

guards to protect the immovable fire hazards andnearby personnel from the heat, sparks and slag.

• Have sufficient fire-extinguishing equipment ready for use when welding and cutting.

• When welding or cutting in areas not normally de

Signed for such operations, use a hot work permitsystem. The hot work permit system includes a check list of safety precautions and also alerts other workersto an extraordinary danger of fire that will exist at aparticular time.

01 welding and cutting safety

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