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Safety and Industrial HygieneSafety Standard Practice

Title Burning and Welding Standard Practice

Owner General Manager Safety & I.H.

Date Issued 11/1/93 Revision Date 02/14/2011 Version

Number 5

1.0Purpose & Scope:1.1 The purpose of this Standard Practice is to provide the minimum basic

requirements for the safe use of burning and/or welding equipment. Adherence to applicable regulatory requirements and facility specific Safe Job Procedures is also required.

1.2 This Standard Practice applies to all U. S. Steel locations, Operating and Other.

2.0References: 2.1 Hot Work Standard Practice

2.2 IH Guideline 19.3 - Non Approved Substance List

2.3 Confined Space Entry Life Threatening Standard Practice

2.4 29 CFR1910.251, through and including 29 CFR1910.255

2.5 ANSI Z49.1

2.6 Hot Tap Safety Standard Practice

2.7 Purging and Blanking Safety Standard Practice

2.8 Tank Cleaning and Maintenance Safety Standard Practice

3.0Appendix: 3.1 Burning Torch Equipment Inspection Procedure

4.0Responsibilities: 4.1 Area Supervisors, Shift Managers, and Crew Leaders are responsible for ensuring

that the requirements set forth in this Standard Practice are adhered to including the storage, set-up, safe use, repair and maintenance of burning and welding equipment.

4.2 Management is responsible for:

4.2.1 Maintaining qualification records;

4.2.2 Verifying that welders have the necessary qualifications to perform assigned welds;

4.2.3 Ensuring necessary qualifications are current;

4.2.4 Implementing a remediation plan if an employee’s ability to satisfactorily weld is in question.

4.3 Employees are responsible for thoroughly executing this procedure when assigned to utilize burning and/or welding equipment.

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5.0Training: 5.1 All personnel who are expected to perform welding and burning duties shall have

the appropriate training before being assigned. This shall include but not be limited to the following personnel:

Maintenance Technician – Electrical

Maintenance Technician – Mechanical

Operational Technician

Other – All other personnel who perform burning or cutting tasks

6.0General Procedure:6.1 All welding or burning on U. S. Steel property shall be conducted in compliance

with the requirements of the following U. S. Steel Standard Practices:

Burning and Welding Standard Practice

Burning Torch Equipment Inspection Procedure

Hot Work Standard Practice

Confined Space Entry Standard Practice

Hot Tap Safety Standard Practice

Purging And Blanking Safety Standard Practice

Tank Cleaning and Maintenance Safety Standard Practice

I.H. Standard Practice 19.3-Non Approved Substance List

Applicable Safe Job Procedures

Standard Specification S-001 Contractor Safety

7.0Personal Protective Equipment7.1 Fire Retardant (FR) PPE will be supplied by the company and be worn when an

employee is working in an area or on a job requiring FR PPE. At minimum, FR PPE will include an orange FR jacket and orange FR pants. Additional FR PPE may include Aluminized jackets/spats/hoods, Norfab jackets/pants, Leather jackets/chaps, FR gloves, or FR snoods.

7.1.1 Areas:7.1.1.1 Coke Ovens7.1.1.2 Blast Furnace Cast House7.1.1.3 BOP/LMF7.1.1.4 Caster7.1.1.5 Steel Shop pits/ladle transfer aisles7.1.1.6 Hot Dip Coating

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7.1.1.7 Other areas where Molten Metal, Molten Slag, or Hot Coke are present

7.1.2 Jobs:7.1.2.1 Hot Work7.1.2.2 Electrical work requiring Arc Flash Protection7.1.2.3 Miscellaneous activity involving molten metal/open flame

7.2 Personal clothing worn beneath company issued FR apparel must be 100% natural fiber (cotton or wool). Clothing made of synthetic materials (acetate, nylon, polyester, polypropylene, spandex, dryfire, etc.) may burn at lower temperatures compared to natural fibers or melt causing an increased injury risk, and are not to be worn under FR apparel with exception of elastic bands or other small amounts of synthetics used in undergarments.

8.0Welding Machines and Power Circuits:8.1 Welding Machines

8.1.1 When lifting portable welding machines with a crane or hoist, always use the lifting rings or attachments designed and provided for this purpose.

8.1.2 When towing portable welding machines, there shall be a secure connection between the trailer and the tow vehicle. Never tow with a cable, sling, or other temporary tow hitch. A safe speed shall be maintained.

8.1.3 Primary Power Supply Circuits

8.1.3.1 Welding machines shall be connected to power lines only at the outlet side of a fused safety switch or circuit breaker. Connection of each electrically driven unit to an individual switch or circuit breaker having a capacity corresponding to the manufacturer's input rating is required. Connection of multiple units to a single fused switch or circuit breaker where the hookup entails the use of multiple conductors sharing a common terminal is permitted.

8.1.3.2 Where plugs and receptacles are not used, only qualified a maintenance technician electrical/mechanical who has been properly trained shall connect or disconnect welding machines to power circuits.

8.1.3.3 The power supply to welding machines or welding transformers shall be shut off when the equipment is to be left unattended, or when the equipment is to be moved. This includes the engines on portable welding machines. Never tow with the engine running on the welder unless a written exception to this requirement has been obtained from the safety department.

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8.1.3.4 Where several welding machines are connected to a common distribution panel, starting and stopping of the machines shall be on a "one-at-a-time" basis and shall not be accomplished by engaging or disengaging plugs from receptacles. Pulling the main disconnect switch must follow the shutoffs of the individual machines.

8.1.3.5 Welding leads must never be used to transmit primary electric power.

8.1.3.6 Extension cords shall be used only in continuous lengths without tape splice connections. Suitable molded or vulcanized splices may be used if properly made by qualified personnel such as a maintenance technician electrical/mechanical.

8.1.4 Equipment Grounding

8.1.4.1 The frame or case of all welding machines, except engine-driven machines, shall be grounded to an earth ground before the machine is connected to a power supply. The grounding conductor shall have a current-carrying capacity at least equal to that of the individual conductors in the power lead to the machine. The return lead must be at least two (2) wire sizes larger than the work lead. It may be either integral with the power cable or it may be a separate conductor.

8.1.4.2 Conductors used for grounding equipment frames shall not be used in a dual grounding capacity, such as a common ground for the welding circuit and an equipment safety ground.

8.1.4.3 An approved earth ground may be accomplished by connecting to any of the following:

8.1.4.3.1 A buried cold water pipe system that is not wrapped or insulated from the earth.

8.1.4.3.2 The metal frame of a building or other structure if effectively grounded.

8.1.4.3.3 A local metallic underground piping system, metal well casing, etc., other than sprinkler systems or piping systems carrying combustible gases or combustible liquids.

8.1.4.3.4 A pipe or conduit of not less than 3/4-inch inside diameter driven to a depth of at least 8-feet. Pipe or conduit shall be galvanized.

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8.1.4.3.5 A ground rod, if steel at least 5/8-inch diameter, if nonferrous materials at least 1/2-inch diameter, driven to a depth of at least 8-feet.

8.1.4.3.5.1 Bolt on type connections are preferred as opposed to clamp type clamp type.

8.1.4.3.5.1.1 When/where bolt on type cannot be used a spring type clamp can be used provided the clamp is stainless steel and has a clamping force greater than 50 PSI.

8.1.4.3.6 In areas where rock is encountered and prevents the driving of adequate ground rods, a buried plate of at least 2 square feet of surface, and at least 1/4-inch thick if made of steel, and 1/16-inch thick if made of nonferrous materials, may be embedded below the permanent moisture level.

8.1.4.4 The ground connection to grounding rods shall be accessible for inspection. The attachment shall be made by means of a bolted clamp.

8.1.4.5 The grounded cable shall be solidly connected to equipment frames, conduits, cabinets, enclosures, and the like by means of approved pressure lugs, connectors, or clamps. Nonconductive coatings, such as paint, shall be removed from threads and other contact surfaces in order to insure a good electrical connection. The ground connector must never be welded to any compression or tension member of building or crane structure.

8.1.4.6 All grounding conductors shall remain connected as long as the power circuit is connected.

8.2 Welding Circuits

8.2.1 Welding Leads

8.2.1.1 Only approved insulated cable conductors shall be used to carry current from the welding machine to the electrode holder and the work.

8.2.1.1.1 Refer to table 1 for required cable sizes.

8.2.1.2 Splices and joints in the cable carrying the welding current shall be secure with stress relief in place and insulated effectively. Cables shall not be used with splices within 10-feet of electrode holder.

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8.2.1.3 Welding cables shall not be left in coils while carrying heavy welding current (300-amps or more) so as to avoid overheating and damage to insulation.

8.2.1.4 Welding cables shall not be left in coils or wrapped around structures to avoid overheating of the wire and inducing stray electrical current into the structure.

8.2.1.5 Terminals for welding leads shall be protected from accidental electrical contact by personnel or by metal objects. Protection may be obtained by the use of dead-front construction utilizing receptacles for plug connections by locating terminals in a recessed opening or under a non-removable hinged cover, by heavy insulating sleeves, or by other equivalent mechanical means.

8.2.2 Welding Grounds

8.2.2.1 Welding ground return systems shall be electrically complete between work and machines and shall not be connected to the power grounding systems, conduits, or power equipment.

8.2.2.2 The welding ground shall be connected as close to the work area as possible. But in no case greater than 8-10 feet. Welding current return circuits or "grounds" must carry their current without hot or sparking contacts, without heating of conductors or their joints, and without passage of current through equipment or structures which might be damaged or made unsafe by the welding current or its voltage. In particular, do not connect grounds to or allow welding current to pass through:

a) Acetylene, fuel gas, oxygen, or other compressed gas cylinders.

b) Tanks or containers used for gasoline, oil, or other flammable liquids.

c) Pipes carrying flammable gases or flammable liquids.

d) Conduits carrying electrical conductors.

e) Chains or wire ropes.

f) Metal handrails or ladders.

g) Machines, shafts, bearings, electric motors, or weighing scales.

h) Crane bridge wheels or trolley wheel bearings.

i) Crane or lifting equipment hooks.

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j) Mobile equipment batteries.

8.2.2.3 Welding current shall be returned to the welding machine by a single cable connecting the work to the machine. The connection of a cable from the welding machine to a common conductor on which the work rests or to which the work is connected is permissible.

8.2.3 Electrode Holder and Electrodes

8.2.3.1 Make sure the current-carrying parts of the electrode holder are insulated effectively.

8.2.3.2 The electrode holder must grip the welding electrode firmly to avoid generation of excessive heat and to avoid arcing between the electrode and holder.

8.2.3.3 That portion of the welding lead attached to the electrode holder, commonly referred to as the whip, shall be at least 10-feet in length, rubber-covered, and free of joints or splices.

8.2.3.4 Electrode holders shall not be dipped in water to cool.

8.2.3.5 Do not handle electrode holders from two different machines at the same time.

8.2.3.6 Electrodes shall be removed from holders when not in use to eliminate danger of electrical contact with persons or conducting objects. Electrodes in wire form in semiautomatic holders shall be cut off short to reduce the possibility of contact.

8.2.3.7 All electrodes shall be secured and stored in warm, dry containers. Low hydrogen (EXX18) electrodes exposed to the atmosphere in excess of four (4) hours shall be placed in a heated oven (200 to 250) to control moisture. All high alloy electrodes (over 80,000 tensile) shall be approved by supervision for each application before use.

8.2.4 Welding Equipment

8.2.4.1 Maintenance technicians electrical/mechanical must not attempt to repair welding machines, welding generators, or welding transformers. Mechanical and/or electrical trouble with the equipment shall be reported to the supervisor or other designated person.

8.2.4.2 The polarity of the welding machine shall not be changed while the machine is under load.

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8.2.4.3 Engine driven welding machines are often used to supply 110 VAC or 220 VAC power for items such as lighting or grinders while working in the field. Supplemental Ground Fault Interruption (GFI) protection shall be utilized if the machine is not already so equipped.

8.3 Protective Equipment

8.3.1 Face and Eye Protection

8.3.1.1 Persons engaged in arc welding must wear a welding helmet or use a hand shield with a colored filter glass to protect from the arc's rays. Helmets are preferred to hand shields.

8.3.1.1.1 Refer to Table 2 for lens shade requirements.

8.3.1.2 Minimum eye protection in the form of safety glasses with side shields shall be worn, beneath the helmet or hand shield, by employees and others working near welding operations.

8.3.1.3 When grinding or scaling welds approved eye protection including safety glasses and a face shield or a welding helmet equipped with an auto darkening or flip up protective lens shall be worn.

8.3.1.4 When burning, the use of approved burning goggles or a properly tinted face shield and safety glasses are required.

8.3.2 Protection of Hands and Other Parts of the Body

8.3.2.1 The hands of persons engaged in arc welding shall be protected from heat, spatter, and arc reflection by approved hand protection. Refer to the corporate and/or plant specific approved personal protective equipment listing for specific details.

8.3.2.2 For arc welding, other parts of the body shall be protected, as necessary, by such means as leather sleeves, flame retardant jackets and trousers, and flame retardant spats or leggings. All clothing shall be non-aluminized type.

8.3.2.3 Maintenance technician electrical/mechanical using any inert gas shielded arc welding process (MIG or TIG) must wear flame retardant non-aluminized clothing that is sufficiently heavy to protect them from the open arc that is characteristic of these processes.

8.3.2.4 For oxygen burning and oxygen/fuel cutting and welding, flame retardant trousers and jackets are required. Refer to job specific SJP to determine if the use of aluminized clothing is mandated.

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8.3.2.5 When plasma arc cutting or performing electric arc welding, flame retardant non-aluminized clothing, including trousers and jackets, are required. The neck opening of the jacket shall be buttoned closed unless the welding hood provides the neck area with protection from radiant UV exposure.

8.3.2.6 Protective equipment such as gloves and clothing shall be kept as dry as possible to avoid electric shock. Suitable protection shall be provided when arc welders are required to work on wet floors or wet ground.

8.3.2.7 Control equipment to automatically reduce the no-load voltage on transformer-type welders so as not to exceed 38 volts RMS (root means square) (AC) or 50 volts direct current (DC) at rated input, is required when welding in “confined spaces” or under “wet conditions”.

8.3.2.7.1 Conditional approval can be given for use of devices that eliminate no-load voltage at the electrode holder after an arc is stopped.

8.3.2.8 Never burn or weld while wearing ragged or excessive oily clothing.

8.3.3 Fall Protection

8.3.3.1 When working on unprotected elevated structures, platforms, scaffolds or runways; workers shall utilize personal fall protection in accordance with the Elevated Work and Fall Prevention Standard Practice.

8.3.3.2 When wearing a safety harness and lanyard, precautions shall be taken to protect the tie-off so that this equipment will not be exposed to spatter or sparks from the torch. All employees utilizing fall protection equipment shall inspect their equipment before each use.

8.3.4 Noise Control

8.3.4.1 Earmuffs or earplugs shall be used when engineering and administrative control methods fail to bring noise exposure within allowable limits.

8.4 Burning Equipment and Gases

8.4.1 Storage and Use of Cylinders

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8.4.1.1 All gas cylinders shall be protected against undue absorption of heat. Cylinders of oxygen shall not be stored in the same compartment with cylinders of acetylene or other fuel gas. Unless separated by at least 20-feet, there shall be a non-combustible barrier, at least 5-feet high, between the oxygen cylinders and acetylene or fuel gas cylinders. The barrier shall have a fire resistance rating of at least one-half hour. Where cylinders are stored in the open, they shall be protected from accumulations of ice and snow.

8.4.1.2 Inside buildings, cylinders shall be stored in a well ventilated and dry location. Cylinders shall be protected from tampering by unauthorized individuals. Storage areas shall not be located near elevators, stairs, or gangways.

8.4.1.3 When in use or stored as part of a portable station, cylinders of oxygen and acetylene or other fuel gases, shall be separated by a non-combustible barrier that is at least 5-feet high with a fire resistance rating of at least one-half hour.

8.4.1.4 Oxygen, air, or any other compressed gas cylinders shall be secured in racks or tied securely at all times when standing in a vertical position.

8.4.1.5 Always stand acetylene cylinders with valve end up.

8.4.1.6 Never use slings or magnets for hoisting cylinders. Use a suitably designed carrier.

8.4.1.7 Cylinders must never be allowed to come in contact with energized wires or electrical equipment ground wires.

8.4.1.8 No attempt shall be made to transfer acetylene from one cylinder to another or to mix gases in a cylinder.

8.4.1.9 Never use cylinders as rollers or supports for burning, cutting, or welding work even if they are considered to be empty. Avoid rough handling, dropping, and bumping.

8.4.1.10 Valves on empty cylinders shall be closed and the valve caps replaced.

8.4.1.11 Empty cylinders shall be marked "MT," segregated from full cylinders, and with valve caps in place, promptly returned to the supplier.

8.4.1.12 Cylinder valves not provided with fixed hand wheels shall have keys or handles on the valve spindles or stems while the cylinders are in service.

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8.4.1.13 A hammer or wrench shall not be used to open cylinder valves. If valves cannot be opened by hand, notify your supervisor or other designated person.

8.4.1.14 Valve caps shall always be in place, hand-tight, except when cylinders are in use, connected for use or not designed for caps.

8.4.1.15 Keep a clear space between the cylinders and the work so that the cylinder valves and the pressure-reducing regulators can always be reached quickly in event of trouble.

8.4.1.16 Cabinets where fuel gas and/or oxygen cylinders are stored shall be properly vented.

8.4.1.17 Leaking cylinders:

8.4.1.17.1 Shall be kept away from flame and sparks.

8.4.1.17.2 Shall be taken outside building away from sources of ignition.

8.4.1.17.3 Shall be tagged and identified to explain trouble.

8.4.1.17.4 The supervisor or other designated person shall be notified immediately.

8.4.1.18 If a fuel gas cylinder catches fire the area shall be vacated and the fire department called immediately.

8.4.2 Manifolds

8.4.2.1 Fuel gas and oxygen manifolds shall have the name of the substance they contain in letters at least 1-inch high painted on the manifold or on a sign permanently attached to it.

8.4.2.2 Fuel and gas oxygen manifolds shall be placed in safe, well ventilated, and accessible locations.

8.4.2.3 Manifolds shall not be located within enclosed areas.

8.4.2.4 Manifold hose connections, including both ends of the supply hose that lead to the manifold, shall be designed so that the hose(s) cannot be interchanged between fuel gas and oxygen manifolds or supply connections.

8.4.2.5 Hose connections shall be kept free of dirt, grease, and oil.

8.4.2.6 Manifold and header hose connections shall be capped when not in use.

8.4.2.7 When in use, nothing shall be placed on top of a manifold which would interfere with the quick closing of the valves or damage the manifold.

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8.4.3 Pressure Regulators

8.4.3.1 Before installing the regulator, "crack" the valve of oxygen and fuel gas cylinders and/or station outlet valves momentarily to clear the valves of any dirt, dust, or other foreign material. Do not stand in front of the valve being opened.

8.4.3.2 Never use gases from cylinders and piped systems without using the proper regulators for reducing the pressure.

8.4.3.3 Never interchange oxygen or fuel gas regulators, hoses, or other burning apparatus. Make certain the hose is secure to the connections and all fittings are tight.

8.4.3.4 Loosen the pressure-adjusting screw of the regulator before opening the cylinder valve. Open the cylinder valves only slightly at first; when the gauge hand has stopped moving, open the oxygen cylinder valve fully. Fuel gas valves should be opened a quarter of a turn. Stand to the side of the regulator and not in front of the glass-covered gauge faces when opening the cylinder valve.

8.4.3.5 If a regulator creeps (that is, pressure builds up after the torch valves are closed), have it repaired at once.

8.4.3.6 Do not make repairs or adjustments to regulators. Repairs shall be performed only by the authorized repair service.

8.4.3.7 Multiple torches shall not be supplied by a single set of gas and oxygen cylinders unless each torch has its own set of shut off valves at the regulator.

8.4.3.8 Multiple torches supplied from a single set of tanks can only be utilized when approved by the supervisor or designate and Safety Department representative.

8.4.4 Hoses and Connections

8.4.4.1 Oxygen and fuel gas hoses shall be easily distinguishable from each other.

8.4.4.2 Hose to torch and hose to regulator connections shall be made with properly threaded connections. Quick disconnect couplings that unlock by means of a straight pull are strictly prohibited.

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8.4.4.3 Protect hoses from damage or interference. Protect hoses from being trampled or run over. Avoid tangles and kinks and place the hoses so that they will not be a tripping hazard. Should a hose become fouled, do not pull on it to free it. Take precautions to prevent hoses from coming in contact with oil or grease and protect the hoses from open flame, sparks, hot slag, or other hot objects.

8.4.4.4 Hoses shall be examined daily for leaks, worn areas, and loose connections. Never try to locate an oxygen or acetylene leak with flame. Use an oil-free leak test solution or soapy water (oil-free dishwashing detergent) and brush. Defective hoses shall be replaced at once. Makeshift repairs are never permissible.

8.4.4.5 In the event of a flashback in the torch, close the oxygen valve at once, then the fuel gas valve. Cool the torch and bleed thoroughly before relighting. In the event of a flashback into the hoses, shut off the oxygen and fuel gas regulators. Remove the burning outfit (including torch, hoses, and regulator) for service and inspection by a qualified person.

8.4.5 Oxygen – Special Precautions

8.4.5.1 Always refer to oxygen by its proper name "OXYGEN" and not by the word "AIR". Oxygen will not burn, but supports and accelerates combustion and will cause oil and other similar materials to burn with great intensity. Oil or grease in the presence of oxygen under pressure may ignite violently.

8.4.5.2 Oil or grease shall never be permitted to come in contact with oxygen cylinders, valves, regulators, hoses, or other fittings. Oxygen cylinders and apparatus shall not be handled with oily hands, gloves, or greasy materials. Should oil or gas enter the valves, fittings, regulators, torches, or hoses, that piece of equipment shall not be used until thoroughly cleaned by an approved procedure.

8.4.5.3 Oxygen shall never be used as a substitute for compressed air. Never use oxygen in pneumatic tools, in oil preheating burners, to start internal combustion engines, to blow out pipelines, in arc-air torches, to dust clothing or work, to create pressure, for ventilation, testing, or other purposes different from its intended function in burning and welding.

8.4.5.4 Oxygen cylinder valves shall be opened fully and top seated when in use to prevent leakage around the valve stem.

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8.4.5.5 Never use oxygen except through an approved oxygen pressure-reducing regulator.

8.4.6 Fuel Gases – Special Precautions

8.4.6.1 Fuel/welding gases shall be referred to by their proper names such as "PROPANE" or "ACETYLENE" or by general classifications such as "LPG," or "FUEL GASES," and not simply as "Gas."

8.4.6.2 Never force thread connections on fuel gas cylinder equipment.

8.4.6.3 Acetylene shall not be brought into contact with unalloyed copper except for specifically approved applications, such as a blowpipe or torch, because copper acetylene, an explosive compound, is produced.

8.4.6.4 A fuel gas cylinder valve shall be opened slightly at first, then no more than one-and-one-half (1-1/2) turns of the spindle.

8.4.7 Flashback Protection

8.4.7.1 Oxygen-Fuel Cutting/Welding Torches

8.4.7.1.1 Flashback arrestors shall be installed at the torch end hose connections for both fuel gas and oxygen lines.

8.4.7.1.1.1 The plant Safety and Industrial Hygiene Department, upon receiving requests and recommendations from plant operating and maintenance, shall review and provide any exceptions to the policy.

8.4.7.1.1.1.1 With appropriate approval, a check valve may be used in lieu of flashback arrestors for high gas volume applications such as scarfing torches.

8.4.7.1.2 Combination Flashback arrestor/thermal shut-off device or thermal shut-off device shall be installed on the regulator side for both fuel gas and oxygen lines. This is required in order to prevent a flashback from potentially traveling to the fuel and/or oxygen source.

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8.4.7.1.3 Flow rate shall be considered when installing flashback arrestors or thermal shut-off devices. High flow rate equipment should be used at the regulator side and is available from select vendors.

8.4.7.1.3.1 Flashback arresters shall be rated for the intended operating flow volume and pressure.

8.4.7.2 Oxygen Cutting/Burning

8.4.7.2.1 A check valve shall be installed at the oxygen lance or burning bar end where anti-slag or thermal shut-off devices are not incorporated into the design of the equipment.

8.4.7.2.2 A thermal shut-off device, flashback arrestor or combination device shall be installed at the oxygen supply end. This is required in order to prevent a flashback from potentially traveling to the oxygen source.

8.4.8 Equipment Inspection

8.4.8.1 Pre-use and semi-annual equipment inspections shall be completed as outlined in the “Burning Torch Equipment Inspection Procedure”. The equipment shall be tagged or labeled with the date of the most recent semi-annual inspection.

8.5 Ventilation for burning and welding

8.5.1 Ventilation and Respiratory Protection

8.5.1.1 Burning and welding operations can normally be performed without mechanical local exhaust ventilation in the open air or in shops that have good, natural ventilation. When burning or welding outdoors, attempt to position yourself with the wind at your back so contaminates generated are carried away from you. To determine if natural /mechanical ventilation is sufficient to maintain contaminants below the allowable limits, contact Industrial Hygiene for personnel monitoring and determination of respiratory protection needs. Experience has shown that burning or welding on “specialty metals”, such as stainless steel, can generate contaminant levels above permissible exposure limits and usually requires mechanical ventilation or the use of respirators.

8.5.1.2 When required, respirator protection applies to all persons in the immediate vicinity of welding or cutting operations.

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8.5.1.3 Certain materials sometimes contained in the consumables, base metals, coatings, or atmospheres of welding or cutting operations, have low permissible exposure limits. All material MSDS’s shall be checked to identify their allowable limits.

8.5.1.4 In the use of cleaning materials, because of their possible toxicity or flammability, appropriate precautions such as manufacturers' instructions shall be followed. Degreasing and other cleaning operations involving flammable cleaners or chlorinated hydrocarbons shall be so located that no vapors from these operations will reach or be drawn into the atmosphere surrounding any welding operation. In addition, trichloroethylene, perchloroethylene, and methylene chloride are not permitted to be used on U. S. Steel property.

8.5.1.5 Protective wire screens on the inlet and exhaust sides of ventilating blowers shall be kept free from foreign material. The screens shall be in place when the blowers are in use. Flexible ventilating hose that becomes dented or damaged shall be reported to your supervisor or other designated person.

8.5.1.6 Motor-driven blowers and exhausters, unless provided with plugs to connect them to power outlet receptacles, shall be connected and disconnected to electric power circuits only by authorized maintenance technician electrical/mechanical or repair persons.

8.5.2 Burning and Welding in Confined Areas

8.5.2.1 For work in confined spaces compliance with all elements of the Confined Space Entry Standard Practice as well as any local requirements is mandatory.

8.5.2.2 When welding or cutting is being performed in any confined space, the gas cylinders and heavy welding or cutting equipment shall be left on the outside. Block heavy portable equipment mounted on wheels to prevent accidental movement.

8.5.2.3 When gas welding or cutting in a confined space, the torch valves shall be closed and the gas supply to the torch positively shut off at some point outside the confined area whenever the torch is not in use to reduce the possibility of gas escaping through leaks or improperly closed valves inside the confined area. For intervals such as lunch periods, break periods, or overnight, the torch shall be removed from the confined space.

8.6 General Safety and Protection of Property

8.6.1 General Safety – Welding

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8.6.1.1 Only authorized persons shall operate welding equipment. An employee shall be re-qualified whenever one of the following conditions occur:

8.6.1.1.1 The employee has been absent from the facility for six months or more.

8.6.1.1.2 It is determined that the employee’s ability to make welds that meet required specifications are in question.

8.6.1.1.3 The criterion in this section does not apply to performing tack welding.

8.6.1.2 Qualification and re-qualification tests are to be performed as required by the American Welding Society (AWS) and may consist of one or more of the following methods:

8.6.1.2.1 Visual Inspection

8.6.1.2.2 Nondestructive Testing (NDT)

8.6.1.2.3 Face, root and side bend

8.6.1.2.4 Reduced Section Tension

8.6.1.2.5 All-Weld-Metal Tension

8.6.1.2.6 Macrotech

8.6.1.3 Qualification records shall be maintained in accordance with U. S. Steel record retention requirements.

8.6.1.4 Welding cable, when in use, must not be looped over the shoulders or around any part of the body.

8.6.1.5 Screens of fire-resistant materials shall be used to protect other workers and passers-by from the arc reflections. Appropriate signage shall be placed in the vicinity of the work area in order to warn people against looking directly at the welding arc.

8.6.1.6 Welding cable, ventilating hose and other equipment shall be clear of possible sources of damage such as metal sparks, high voltage power cables, steam lines, moving shafts or machinery, and also passageways, ladders, and stairs.

8.6.1.7 Position welding cable, ventilation hose, and working materials so as to not create tripping hazards.

8.6.1.8 Only qualified maintenance technicians (electrical/mechanical) shall weld supports for staging or scaffolding or make welds attaching lifting hitches, pads, or lugs with the approval of plant engineering.

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8.6.1.9 Welding electrode stubs must not be discarded on floors, decks, staging, and scaffolds. They shall be collected in a suitable labeled container for safe disposal. All unused electrodes shall be removed from the work site and placed in labeled containers at a designated storage area at the completion of a job or at the end of turn.

8.6.1.10 Employees shall inspect the area in which they are to work to be sure that it is clear of objects which might fall or which otherwise might cause injury when vision is obstructed by the welding helmet.

8.6.1.11 Electrodes shall be carried in a rod bag or similar carrier. Electrodes shall be kept dry and clean.

8.6.1.12 Before starting operations, a maintenance technician electrical/mechanical shall make certain that all electrical connections are properly made. The work piece or metal upon which the piece rests shall be grounded independent of the welding leads. A ground test shall be performed. Work leads shall be as short as possible.

8.6.1.13 Maintenance technicians electrical/mechanical must comply with established Safe Job Procedures to avoid shock when changing welding electrodes in the electrode holder. Don't stand in water. When handling the electrode holder or cable, the technician must avoid electrical contact between his/her body and objects connected to the work or "ground" side of the welding circuit.

8.6.1.14 Maintenance technician electrical/mechanical must comply with any applicable Welding Procedure Specifications.

8.6.1.15 Any discomfort or injury to the eyes or other parts of the body caused by reflection from the arc or by weld slag or scale shall be reported to the supervisor or other designated person and the welder shall obtain medical treatment.

8.6.2 General Safety – Burning

8.6.2.1 Only trained and authorized maintenance technician electrical/mechanical, operations technician/other employees shall operate burning equipment.

8.6.2.2 Inspect torches, hoses, lances, regulators, and other apparatus before use to make certain each is in good order. The employee shall report any deficiencies to their supervisor tag the equipment “Out of Service” and remove equipment from service until repairs are made.

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Number 5

8.6.2.3 A semi-annual inspection shall be made and documented utilizing the Burning Equipment Inspection Checklist.

8.6.2.4 Always use a standard friction-spark lighter or stationary pilot flame as an ignition source. Do not use a match, cigarette, cigarette lighter or hot material (ignition may be violent if delayed) to light or relight a torch.

8.6.2.5 The protective caps on piped oxygen (Driox) and natural gas valve outlets shall be in place when the burning outfit is disconnected. Report missing caps to your supervisor or other designated person.

8.6.2.6 Burning hose must not be draped over shoulders or put between the legs while burning.

8.6.2.7 When stopping work, close the valve on the cylinder or pipeline and release the pressure in the regulator and hose. Make certain the torch is not burning when not in use and that the valves are tightly closed.

8.6.2.8 Take necessary precautions when burning on a concrete floor due to the possibility of exploding the concrete. Raise material to be cut sufficiently to protect the floor. Alternate approved methods of floor protection may be used if an adequate safe distance between the floor and the work cannot be maintained.

8.6.2.9 When burning any material, be sure you will not loose your balance or fall when the piece is burned through. Also, ensure that the material will not fall or swing towards you or others.

8.6.3 Burning and Welding in the Presence of Combustible, Flammable, or Explosive Materials

8.6.3.1 No burning or welding shall be done on, in, or near areas where there may be gases, vapors, fumes, mists, liquids or materials that are combustible, flammable, or explosive without first meeting the requirements of the Hot Work Standard Practice and applicable local requirements.

8.6.3.2 No burning or welding is to be done on or in a tank, pipeline, compartment, or container until the area management has positively identified the contents and all requirements of the Hot Work Standard Practice, the Purging and Blanking Standard Practice, the Tank Cleaning and Maintenance Standard Practice, the Confined Space Entry Standard Practice and applicable local requirements have been met.

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Number 5

8.6.3.3 Affected employees must perform a thorough “Danger Zone” assessment of the area to recognize and properly address all identified hazards prior to starting to burn or weld.

8.6.3.4 Never open the valve of any oxygen or fuel gas cylinder near any potential ignition source such as sparks, flame, or other welding or cutting work.

8.6.3.5 Burning or welding is not permitted in areas where spray-painting activities are in progress unless all requirements of the Hot Work Standard Practice and applicable local requirements have been met.

8.6.3.6 When burning/welding on propane operated mobile equipment, remove the tanks before starting burning/welding operations. Gasoline or other fuel tanks shall be removed from vehicles or they shall be emptied and purged before any burning or welding is performed on the vehicle. In the case of liquid fuel tanks, with specific supervisor approval, burning or welding may be performed if the fuel tank is full, if all openings are sealed, and if the burning or welding is at least 12-inches from any part of the fuel system. In all cases, a fire- and spark-resistant shield shall be placed between the point of burning or welding and any nearby portion of the fuel system. In arc welding operations, the welding current return cable or "ground" shall be connected firmly to the part of the vehicle that is being welded. There shall be a dry-powder fire extinguisher at the site until the work is completed.

8.6.3.7 Terminal leads shall be removed from the battery when arc welding is to be performed on any part of the vehicle regardless of distance from the battery. Batteries shall be removed from vehicles before any welding or burning is performed within 18-inches of the battery. If burning or welding is performed within the engine compartment or in the area within which the battery is positioned, but beyond 18-inches, a fire and spark-resistant shield shall be placed between the point of burning or welding and the battery, and both terminal leads shall be removed.

8.6.3.8 Welding machines shall not be used to "jump-start" vehicles.

8.6.4 Protection of Property

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Number 5

8.6.4.1 No burning or welding shall be done on EOT cranes, lifting devices, structural support components, or parts of steel structures such as ore bridges, coal bridges, gantry cranes, vessel loaders, and un-loaders without authorization from your supervisor and the Engineering Department.

8.6.5 Shutting Down Equipment

8.6.5.1 First close the torch oxygen "OX" valve, and then close the torch fuel "GAS" valve. This sequence will prevent flame from popping out at shut down.

8.6.5.2 Close the “OX” cylinder valve, then the fuel “GAS” cylinder valve.

8.6.5.3 Bleed off all oxygen at torch "OX" valve, and then close the valve.

8.6.5.4 Bleed off all fuel gas at torch "GAS" valve, and then close the valve.

8.6.5.5 All pressure gauges must read "0" PSI. Turn both pressure regulator adjusting keys counter clockwise until loose.

8.6.6 Transporting Cylinders

8.6.6.1 All cylinders will be transported in a vertical position, secured by chains or other devices to keep cylinders upright.

8.6.6.2 Valves on fuel gas and oxygen cylinders will be closed, and hoses and regulators depressurized as per section 8.6.5.

8.6.6.3 Regulators and hoses can remain attached if the vehicle compartment in which the fuel gas and oxygen cylinders are secured provides adequate protection for the regulators. As required in section 8.4.1.3, cylinders of fuel gas and oxygen shall be separated by a non-combustible barrier that is at least 5-feet high with a fire resistance rating of at least one-half hour

8.6.6.4 If the vehicle in which the cylinders are secured must travel off of plant property on public roadways, all DOT requirements for the transport or pressurized fuel gas and oxygen cylinders apply. Regulators and hoses removed, properly secured and caps in place.

8.6.6.5 Retractable hose reels for oxygen and fuel gas hoses shall be specifically designed for burning hose use, with the separated swivels for the two gases.

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Number 5

8.6.6.6 Reels shall be permanently mounted on the service vehicle. The hose reels are subject to the same 6-month inspection, by a qualified person, as the torches and regulators.

8.6.6.6.1 A tag with the inspection dates shall be attached to the retractable hose reel.

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Number 5

TABLE 1The following tables set forth cable sizes for arc welding machines based on safe

operating temperatures shall be followed:

Welding Current, Amp.Cable Size No.

CopperCable Size No.

Aluminum

100 4 4

150 3 2

200 2 0

300 1/0 3/0

400 2/0 4/0

500 2/0 --

600 3/0 --WELDING CABLE SIZE SELECTION GUIDE

Distance from welding equipment (Feet)

AMPS 50 75 100 125 150 200 250 300 350

100

150

200

250

300

350

400

450

500

550

4 4 2 1 1/0 2/0 3/0 4/0 4/0

3 2 1/0 1/0 2/0 4/0

2 1/0 2/0 3/0 4/0

1 1/0 3/0 4/0

1/0 2/0 4/0

2/0 3/0 4/0

3/0 4/0 Notes: Distances shown are half the length of cable required. For total cable length of welding lead and 3/0 4/0 ground lead double the distance shown 4 volts Max drop. Normal DC Res @ 25oC 4/0 per ICEA S-19-81 Table 7.5.1

4/0

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TABLE 2FILTER LENSES FOR PROTECTION AGAINST RADIANT ENERGY

Operations Electric Size 1/32 in.

Arc Current (amps)

Minimum* Protective Shade

Shielded metal arc welding

Less than 3

3 - 5

5 - 8

More than 8

Less than 60

60 - 160

160 - 250

250 - 550

7

8

10

11

Gas metal arc welding and flux cored arc

welding

Less than 60

60 - 160

160 - 250

250 - 500

7

10

10

10

Gas Tungsten arc welding

Less than 50

50 - 150

150 - 500

8

8

10

Air carbon

Arc cutting

Light

Heavy

Less than 500

500 - 1000

10

11

Plasma arc welding Less than 20

20 - 100

100 - 400

400 - 800

6

8

10

11

Plasma arc cutting Light**

Medium**

Heavy**

Less than 300

300 - 400

400 - 800

8

9

10

Torch soldering

Torch brazing

Carbon arc welding

2

3

14

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Number 5

Operations Plate Thickness – inches

Thickness – mm Minimum * Protective Shade

Gas Welding:

-Light

-Medium

-Heavy

Under 1/8

1/8 to 1/2

Over 1/2

Under 3.2

3.2 to 12.7

Over 12.7

4

5

6

Oxygen Cutting:

-Light

-Medium

-Heavy

Under 1

1 to 6

Over 6

Under 25

25 to 150

Over 150

3

4

5

* As a rule of thumb, start with a shade that is too dark to see the weld zone. Then go to a lighter shade which gives sufficient view of the weld zone without going below the minimum. In oxyfuel gas welding or cutting where the torch produces a high yellow light, it is desirable to use a filter lens that absorbs the yellow or sodium line in the visible light of the (spectrum) operation.

** These values apply where the actual arc is clearly seen. Experience has shown that lighter filters may be used when the arc is hidden by the work piece.

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REVISION REGISTER

Date Description of Change Page No. Initials

7/23/07 Initial Version on file in Safety & IH Department All

7/31/07 CSST Review / Revision All KF

06/24/08 Changed language for flash back protection and oxygen cutting.

Added Table 2 “Filter Lenses for Protection Against Radiant Energy”

Added section on Manifolds

11,

19,

9

MAS

03/05/10 Added language regarding manager responsibilities and welder testing requirements.

1,

13,

14

KF

04/08/10 Added Reference ANSI Z49.1, Hot Tap, Purging and Blanking, Tank Cleaning and Maintenance

1 WAS

04/08/10 Added Section 4.2 Additional Management Training Responsibilities

1 WAS

04/08/10 Added Section 5.2 added. General Training Requirements 3 WAS

04/08/10 Added Section 7.1.3.1, 7.1.3.5.1, 7.1.3.5.2 & 7.2.2.2 Grounding

4 ,5 & 7 WAS

04/08/10 Added Section 7.2.1.4 Welding Leads 6 WAS

04/08/10 Revised Section 7.6.1.1 – Revised qualifications 15 & 16 WAS

04/08/10 Added Section 7.6.1.11 Grounds Testing added 17 WAS

04/08/10 Added Section 7.6.3.1.1 Additional language burning / welding in the vicinity of combustible / flammables

18 WAS

04/08/10 Added to Table I 21 WAS

02/14/11 Added Section 7 – Personal Protective Equipment 2 mas

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