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SPECIFICATION FOR TUNGSTEN AND TUNGSTEN-
ALLOY ELECTRODES FOR ARC WELDING AND
CUTTING
SFA-5.
(Identical with AWS Specification A5.12/A5.12M-98)
1. Scope
This specification prescribes the requirements for the classification of bare tungsten and tungsten-alloy electrodes for gas tungsten arc welding and cutting and plasma arc welding and cutting.
PART A — GENERAL REQUIREMENTS
2. Normative References
2.1 The following ANSI/AWS standards 1 are refer- enced in the mandatory sections of this document: (a) ANSI/AWS A1.1, Metric Procedure Guide for the Welding Industry. (b) ANSI/AWS A5.01, Filler Metal Procurement Guidelines. (c) ANSI/ASC Z49.1, Safety in Welding, Cutting, and Allied Processes (published by AWS).
2.2 The following ASTM standards 2 are referenced in the mandatory sections of this document: (a) ASTM F288, Specification for Tungsten Wire for Electron Devices and Lamps. (b) ASTM E29, Practice for Using Significant Digits in Test Data to Determine Conformance with Specifica- tions.
(^1) AWS Standards can be obtained from the American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126. (^2) ASTM Standards may be obtained from the American Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.
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2.3 The following ISO standard 3 is referenced in the mandatory section of this document: (a) ISO 6848, Tungsten Electrodes for Inert Gas Shielded Arc Welding and for Plasma Cutting and Welding.
3. Classification 3.1 The tungsten and tungsten-alloy electrodes cov- ered by this specification are classified using a system that is independent of the U.S. Customary Units and the International System of Units (SI). Classification is according to the chemical composition of the electrode as specified in Table 1. See Annex A7 for classification descriptions.
3.2 Electrodes classified under one classification shall not be classified under any other classification in this specification.
3.3 No electrode meeting the requirements of any other classification, shall be classified under EWG.
3.4 The electrodes classified under this specification are intended for gas tungsten arc welding (GTAW), gas tungsten arc cutting (GTAC), plasma arc welding (PAW) or plasma arc cutting (PAC), but that is not to prohibit their use with any other process for which they are found suitable.
(^3) ISO Standards may be obtained from The American National Standards Institute (ANSI), 11 West 42nd Street, New York, NY
A
SFA-5.12 1998 SECTION II
TABLE 1 CHEMICAL COMPOSITION REQUIREMENTS FOR ELECTRODES a
Weight Percent W Other Oxides AWS UNS Min. Or Elements, Classification Numberb^ (difference) c^ CeO 2 La 2 O 3 ThO 2 ZrO 2 Total EWP e^ R07900 99.5 — — — — 0. EWCe-2e^ R07932 97.3 1.8–2.2 — — — 0. EWLa-1e^ R07941 98.3 — 0.8–1.2 — — 0. EWLa-1.5 R97942 97.8 — 1.3–1.7 — — 0. EWLa-2 R07943 97.3 — 1.8–2.2 — — 0. EWTh-1e^ R07911 98.3 — — 0.8–1.2 — 0. EWTh-2e^ R07912 97.3 — — 1.7–2.2 — 0. EWZr-1e^ R07920 99.1 — — — 0.15–0.40 0. EWGd^ — 94.5 - - - - - - - - - - NOT SPECIFIED - - - - - - - - - - 0.
NOTES: a. The electrode shall be analyzed for the specific oxides for which values are shown in this table. If the presence of other elements or oxides is indicated in the course of this work, the amount of those elements or oxides shall be determined to ensure that their total does not exceed the limit specified for “Other Oxides or Elements, Total” in the last column of the table. b. SAE/ASTM Unified Numbering System for Metals and Alloys. c. Tungsten content shall be determined by subtracting the total of all specified oxides and other oxides and elements from 100%. d. Classification EWG must contain some oxide or element additive and the manufacturer must identify the type and nominal content of the oxide or element additive. e. See Table A2 for closely matching grades in ISO 6848.
4. Acceptance
Acceptance 4 of the electrodes shall be in accordance with the provisions of ANSI /AWS A5.01, Filler Metal Procurement Guidelines.
5. Certification
By affixing the AWS specification and classification designations to the packaging, or the classification identification to the product, the manufacturer certifies that the product meets the requirements of this specifi- cation. 5
6. Units of Measure and Rounding-Off Procedure 6.1 This specification makes use of both U.S. Custom- ary Units and the International System of Units (SI). The measurements are not exact equivalents; therefore each system must be used independently of the other without combining in any way. The specification with
(^4) See Section A3, Acceptance (in the Annex) for further information concerning acceptance, testing of material shipped, and ANSI /AWS A5.01, Filler Metal Procurement Guidelines. (^5) See Section A4, Certification (in the Annex) for further information concerning certification and the testing called for to meet this requirement.
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the designation A5.12 uses U.S. Customary Units. The specification A5.12M uses SI Units. The latter are shown in appropriate columns in tables or within brackets [ ] when used in the text.
6.2 For the purpose of determining conformance with this specification, an observed or calculated value shall be rounded ‘‘to the nearest unit’’ in the last right-hand place of figures used in expressing the limiting value in accordance with the rounding-off method given in ASTM E29, Standard Practice for Using Significant Digits in Test Data to Determine Conformance With Specifications.
PART B — TEST, PROCEDURES, AND
REQUIREMENTS
7. Summary of Test Chemical analysis of the electrode is the only test required for classification of a product under this speci- fication. Electrodes must also meet the dimensional, surface finish, and identification requirements estab- lished in this specification.
SFA-5.12 1998 SECTION II
TABLE 2 STANDARD SIZES AND LENGTHS
Size Length
Diameter Tolerance^ a^ Diameter^ Tolerance^ a^ Length Tolerance^ a^ Length^ Tolerance^ a in.^6 in.^ mm^^6 mm^ in.^6 in.^ mm^ mm 0.010 0.001 50 b^6 1. 0.300 0.025 3 1 ⁄ 16 75 b^ −1.0, +2. 0.020 0.002 0.50 b^ 0.05 6 1 ⁄ 16 150 b^ −1.0, +4. 0.040 0.002 1.00 b^ 0.05 7 1 ⁄ 8 175 b^ −1.0, +6. 0.060 c^ 0.002 12 1 ⁄ 8 305 6 3. 1.60 b^ 0.05 18 1 ⁄ 8 455 6 3. 2.00 b^ 0.05 24 1 ⁄ 8 610 6 3. 0.093 ( 3 ⁄ 32 ) 0.003 2.40 0. 2.50 b^ 0. 3.00 0. 0.125 ( 1 ⁄ 8 ) 0.003 3.20 b^ 0. 0.156 ( 5 ⁄ 32 ) 0.003 4.00 b^ 0. 0.187 ( 3 ⁄ 16 ) 0.003 4.80 0. 5.00 b^ 0. 0.250 ( 1 ⁄ 4 ) 0.003 6.40 0. 8.00 b^ 0.
NOTES: a. Tolerances, other than those listed, may be supplied as agreed upon between supplier and user. b. Standard sizes and lengths in ISO 6848, though tolerances differ in some cases. c. Although the metric size 1.6 mm (0.063 in.) is closer to 1 ⁄ 16 in. (0.0625 in.), it has been common industry practice to refer to the U.S. customary size 0.060 in. as 1 ⁄ 16 in.
FIG. 1 MEASUREMENT PROCEDURE FOR STRAIGHTNESS
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TABLE 3 ELECTRODE IDENTIFICATION REQUIREMENTS a,b
AWS Classification Color EWP Green c EWCe-2 Orange EWLa-1 Black c EWLa-1.5 Gold EWLa-2 Blue EWTh-1 Yellow c EWTh-2 Red c EWZr-1 Brown c EWG Gray NOTES: a. The actual color may be applied in the form of bands, dots, etc., at any point on the surface of the electrode. b. The method of color coding used shall not change the diameter of the electrode beyond the tolerances permitted. c. Color code agrees with ISO 6848.
PART C — SPECIFICATIONS FOR WELDING RODS, ELECTRODES, AND FILLER METALS SFA-5.
the type and nominal content of the oxide addition shall also be marked on the package) (b) Supplier’s name and trade designation (c) Size and net quantity (d) Lot, control, or heat number 16.2 Marking of any, or all, overpacking of unit packages with items listed in 16.1 shall be optional with the manufacturer.
16.3 The following precautionary information (as a minimum) shall be prominently displayed in legible print on all packages of the electrodes, including individ- ual unit packages enclosed within a larger package:
WARNING:
Protect yourself and others. Read and under-
stand this information.
FUMES AND GASES can be dangerous to your
health.
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ARC RAYS can injure eyes and burn skin.
ELECTRIC SHOCK can KILL.
O Before use, read and understand the manufacturer’s instructions, Material Safety Data Sheets (MSDSs), and your employer’s safety practices. O Keep your head out of the fumes. O Use enough ventilation, exhaust at the arc, or both, to keep fumes and gases away from your breathing zone and the general area. O Wear correct eye, ear, and body protection. O Do not touch live electrical parts. O See American National Standard ANSI/ASC Z49.1, Safety in Welding, Cutting, and Allied Processes, published by the American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126; and OSHA Safety and Health Standards , 29 CFR 1910, avail- able from the U.S. Government Printing Office, Washington, DC 20402.
DO NOT REMOVE THIS INFORMATION
PART C — SPECIFICATIONS FOR WELDING RODS, ELECTRODES, AND FILLER METALS SFA-5.
sufficient detail to permit the Committee on Filler Metals or the Subcommittee to determine whether the new classification is more appropriate, and whether either is necessary to satisfy the need. The request needs to state the variables and their limits, for such a classification or modification. The request should contain some indication of the time by which completion of the new classification or modification is needed. (3) The request should be sent to the Secretary of the Committee on Filler Metals at AWS Headquarters. Upon receipt of the request, the Secretary will: (a) Assign an identifying number to the request. This number will include the date the request was received. (b) Confirm receipt of the request and give the identification number to the person who made the request. (c) Send a copy of the request to the Chairman of the Committee on Filler Metals and the Chairman of the particular Subcommittee involved. (d) File the original request. (e) Add the request to the log of outstanding requests. (4) All necessary action on each request will be completed as soon as possible. If more than 12 months lapse, the Secretary shall inform the requestor of the status of the request, with copies to the Chairpersons of the Committee and of the Subcommittee. Requests still outstanding after 18 months shall be considered not to have been answered in a ‘‘timely manner’’ and the Secretary shall report these to the Chair of the Committee on Filler Metals for action. (5) The Secretary shall include a copy of the log of all requests pending and those completed during the preceding year with the agenda for each meeting of the Committee on Filler Metals. Any other publication of requests that have been completed will be at the option of the American Welding Society, as deemed appropriate.
A3. Acceptance
Acceptance of all welding materials classified under this specification is in accordance with ANSI /AWS A5.01, Filler Metal Procurement Guidelines, as the specification states. Any testing a purchaser requires of the supplier, for material shipped in accordance with this specification, shall be clearly stated in the purchase order, according to the provisions of ANSI /AWS A5.01. In the absence of any such statement in the purchase order, the supplier may ship the material with whatever testing is normally conducted on the material of that classification, as specified in Schedule F, Table 1, of
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ANSI /AWS A5.01. Testing in accordance with any other Schedule in that Table must be specifically re- quired by the purchase order. In such cases, acceptance of the material shipped will be in accordance with those requirements.
A4. Certification The act of placing the AWS specification and classi- fication designations on the packaging enclosing the product, or the classification identification on the product itself, constitutes the supplier’s (manufacturer’s) certifi- cation that the product meets all of the requirements of the specification. The only testing requirement implicit in this certifica- tion is that the manufacturer has actually conducted the test required by the specification on material that is representative of that being shipped, and that that material met the requirements of the specification. Rep- resentative material, in this case, is any production run of that classification using the same formulation. ‘‘Certification’’ is not to be construed to mean that tests of any kind were necessarily conducted on samples of the specific material shipped. Tests on such material may or may not have been conducted. The basis for the ‘‘certification’’ required by the specification is the classification test of ‘‘representative material’’ cited above, and the ‘‘Manufacturer’s Quality Assurance Program’’ in ANSI /AWS A5.01. Electrodes sold as a standard size must also meet the dimensional, surface finish, and identification re- quirements established in this specification.
A5. Ventilation During Welding A5.1 Five major factors govern the quantity of fumes in the atmosphere to which welders and welding operators are exposed during welding: (1) Dimensions of the space in which welding is done (with special regard to the height of the ceiling) (2) Number of welders and welding operators work- ing in that space (3) Rate of evolution of fumes, gases, or dust, ac- cording to the materials and processes involved (4) The proximity of the welders or welding operators to the fumes, as the fumes issue from the welding zone, and to the gases and dusts in the space in which they are working (5) The ventilation provided to the space in which the welding is done. A5.2 American National Standard ANSI/ASC Z49.1, Safety in Welding, Cutting, and Allied Processes (pub-
SFA-5.12 1998 SECTION II
TABLE A TYPICAL CURRENT RANGES FOR TUNGSTEN ELECTRODES a
Amperes
Electrode DCEN DCEP Alternating Current Alternating Current Diameter (DCSP) (DCRP) Unbalanced Wave Balanced Wave in. mm EWX-X EWX-X EWP EWX-X EWP EWX-X
0.010 0.30 Up to 15 na b^ Up to 15 Up to 15 Up to 15 Up to 15 0.020 0.50 5-20 na 10–20 5–20 5–15 5– 0.040 1.00 15–80 na 20–60 15–80 10–30 20– 0.060 1.60 70–150 10–20 50–100 70–150 30–80 60– 0.093 2.40 150–250 15–30 100–160 140–235 60–130 100– 0.125 3.20 250–400 25–40 150–200 225–325 100–180 160– 0.156 4.00 400–500 40–55 200–275 300–400 160–240 200– 0.187 4.80 500–750 55–80 250–350 400–500 190–300 290– 0.250 6.40 750–1000 80–125 325–450 500–630 250–400 340–
NOTES: a. All are values based on the use of argon gas. Other current values may be employed depending on the shielding gas, type of equipment and application. b. na p not applicable
lished by the American Welding Society), discusses the ventilation that is required during welding and should be referred to for details. Attention is drawn particularly to the section of that document on Health Protection and Ventilation.
A6. Operation Characteristics
A6.1 The choice of an electrode classification, size, and welding current is influenced by the type and thickness of the base metals being welded. The capacity of tungsten electrodes to carry current is dependent upon numerous factors in addition to the classification and size, including type and polarity of the current, the shielding gas used, the type of equipment (air or water cooled), the extension of the electrode beyond the collet (sleeve or tube that holds the electrode), and the welding position. An electrode of a given size will have its greatest current-carrying capacity with direct current, electrode negative (straight polarity), less with alternating current, and still less with direct current, electrode positive (reverse polarity). Table A1 lists some typical current values that may be used with argon shielding gas. However, the other factors men- tioned above should be carefully considered before selecting an electrode for a specific application.
A6.2 Tungsten has an electrical conductivity that is about 30% that of copper and a thermal conductivity which is 44% that of copper. Therefore, there will be more heating as current is passed through the tungsten
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electrode. When welding with tungsten electrodes, the arc tip should be the only hot part of the electrode; the remainder should be kept as cool as possible.
A6.3 One method of preventing electrode overheating is to keep the extension of the electrode from the collet short. If the extension is too long, even a relatively low current can cause the electrode to overheat and melt above the terminus of the arc. Conversely, if the current density is too low, the arc will be erratic and unstable.
A6.4 Many electrode classifications contain emissive oxide additions. These additions lower the temperature at which the electrode emits electrons, to a temperature below the melting point of tungsten. Such an electrode operates cooler, or it can operate at higher currents as will be noted from Table A1. Benefits of these additions include easier starting, particularly when using superim- posed high frequency, more stable operation, and re- duced contamination. These benefits are noted in the description listed for the various classifications con- taining oxide additives.
A6.5 All tungsten electrodes may be used in a similar manner. However, electrodes of each classification have distinct advantages with respect to other classifications. The following section discusses the specific electrode classifications with regard to their operating characteris- tics and usability.
SFA-5.12 1998 SECTION II
risk of internal exposure. Consequently, it is necessary to use local exhaust ventilation to control the dust at the source, complemented if necessary by respiratory protective equipment. The risk of internal exposure during welding is considered negligible since the elec- trode is consumed at a very slow rate. ‘‘Precautions must be taken in order to control any risks of exposure during the disposal of dust from grinding devices. ‘‘The above statement is based on a considered view of the available reports. Commission VIII will continue to keep these aspects under review.’’
A7.4.1 EWTh-1 Electrode Classification (Yel- low). These electrodes were designed for direct current applications. They have the thoria content dispersed evenly throughout their entire length. They maintain a sharpened point well, which is desirable for welding steel. They can be used on alternating current work, but a satisfactory balled end, which is desirable for the welding of nonferrous materials, is difficult to maintain.
A7.4.2 EWTh-2 Electrode Classification (Red). The higher thoria content in the EWTh-2 electrode causes the operating characteristic improvements to be more pronounced than in the lower thoria content EWTh-1.
A7.4.3 Should it be desired to use these electrodes for alternating current welding, then balling can be accomplished by briefly, and carefully, welding with direct current electrode positive prior to welding with alternating current. During alternating current welding, the balled end does not melt and so emission is not as good as from a liquid ball on an EWP electrode.
A7.5 EWZr-1 Electrode Classification (Brown). The EWZr-1 electrode is a tungsten electrode containing zirconium oxide, referred to as zirconia. This electrode is preferred for applications where tungsten contamina- tion of the weld must be minimized. This electrode performs well when used with alternating current as it retains a balled end during welding and has a high resistance to contamination.
A7.6 EWG Electrode Classification (Gray). The EWG electrode is a tungsten electrode containing an unspecified alloy addition. The purpose of the addition is to affect the nature or characteristics of the arc, as defined by the manufacturer. Although no alloy addition is specified, the manufacturer must identify any specific additions and the nominal quantities added.
A8. General Recommendations These recommendations, when followed, should maintain high weld quality and promote welding econ- omy in any specific application.
A8.1 The appropriate current (type and magnitude) should be selected for the electrode size to be used. Too great a current will cause excessive melting, dripping, or volatilization of the electrode. A welding current which is too low to properly heat the electrode tip may cause instability of the welding arc or inability to maintain a welding arc. A8.2 The electrode should be properly cut and ground tapered by following the supplier’s suggested proce- dures. Breaking for severing an electrode is not recom- mended since it may cause a jagged end or a bent electrode, which usually results in a poorly shaped arc and excessive electrode heating.
A8.3 The electrodes should be handled carefully and kept as clean as possible. To obtain maximum cleanli- ness, they should be stored in their original package until used.
A8.4 The shielding gas flow should be maintained until the electrode has cooled. When the electrodes are properly cooled, the arc end will appear bright and polished. When improperly cooled, the end may oxidize and appear to have a colored film which can, unless removed, adversely affect the weld quality on subse- quent welds. All connections, both gas and water, should be checked for tightness. Oxidized, discolored, or otherwise contaminated electrodes will cause difficult arc starting and may prevent starting depending upon conditions and the arc starting method used. A8.5 The electrode extension within the gas shielding pattern should be kept to a minimum, generally dictated by the application and equipment. This is to ensure protection of the electrode by the gas even at low gas flow rates.
A8.6 The equipment and, in particular, the shielding gas nozzle should be kept clean and free of weld spatter. A dirty nozzle adversely influences the gas shielding. This contributes to improper gas flow patterns and arc wandering, which can result in poor weld quality. It may also contribute to excessive electrode consumption.
A9. Discontinued Classifications The EWTh-3 classification was discontinued in the ANSI/AWS A5.12-92 revision of this specification, as
PART C — SPECIFICATIONS FOR WELDING RODS, ELECTRODES, AND FILLER METALS SFA-5.
TABLE A COMPARABLE CLASSIFICATIONS IN ISO 6848 STANDARD AWS Classification ISO Codification EWP (green) WP (green) EWCe-2 (orange) WC 20 (gray) EWLa-1 (black) WL 10 (black) EWLa-1.5 (gold) EWLa-2 (blue) EWTh-1 (yellow) WT 10 (yellow) EWTh-2 (red) WT 20 (red) EWZr-1 (brown) WZ 3 (brown) EWG (gray)
having no commercial significance. For information about this classification, the user is referred to the ANSI/AWS A5.12-80 revision.
A10. International Classifications
The international standard, ISO 6848, classifies many of the grades in this specification. The compositions are virtually the same, though the limits differ slightly in some cases. The classification designations of the corresponding grades are shown in Table A2. Table 2 indicates the standard metric sizes and lengths which correspond to sizes which appear in the ISO standard. Table 3 indicates the classifications which bear the same color marking.
A11. General Safety Considerations
A11.1 Burn Protection. Molten metal, sparks, slag, and hot work surfaces are produced by welding, cutting, and allied processes. These can cause burns if precau- tionary measures are not used. Workers should wear protective clothing made of fire-resistant material. Pant cuffs, open pockets, or other places on clothing that can catch and retain molten metal or sparks should not be worn. High-top shoes or leather leggings and fire-resistant gloves should be worn. Pant legs should be worn over the outside of high-top shoes. Helmets or hand shields that provide protection for the face, neck, and ears, and a head covering to protect the head should be used. In addition, appropriate eye protec- tion should be used. When welding overhead or in confined spaces, ear plugs to prevent weld spatter from entering the ear canal should be worn in combination with goggles or equivalent to give added eye protection. Clothing should be kept free of grease and oil. Combustible materials
should not be carried in pockets. If any combustible substance has been spilled on clothing, a change to clean, fire-resistant clothing should be made before working with open arcs or flame. Aprons, cape-sleeves, leggings, and shoulder covers with bibs designed for welding service should be used. Where welding or cutting of unusually thick base metal is involved, sheet metal shields should be used for extra protection. Mechanization of highly hazardous processes or jobs should be considered. Other personnel in the work area should be protected by the use of noncombustible screens or by the use of appropriate protection as described in the previous paragraph. Before leaving a work area, hot workpieces should be marked to alert other persons of this hazard. No attempt should be made to repair or disconnect electrical equipment when it is under load. Disconnection under load produces arcing of the contacts and may cause burns or shock, or both. ( Note: Burns can be caused by touching hot equipment such as electrode holders, tips, and nozzles. Therefore, insulated gloves should be worn when these items are handled, unless an adequate cooling period has been allowed before touching.) The following sources are for more detailed informa- tion on personal protection: (a) ANSI/ASC Z41.1, Safety-Toe Footwear, Ameri- can National Standards Institute, 11 West 42nd Street, 13th Floor, New York, NY 10036. (b) ANSI/ASC Z49.1, Safety in Welding, Cutting, and Allied Processes. American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126. (c) ANSI/ASC Z87.1, Practice for Occupational and Educational Eye and Face Protection, American Na- tional Standard Institute, 11 West 42nd Street, 13th Floor, New York, NY 10036. (d) Code of Federal Regulations , Title 29, Labor, Chapter XVII, Part 1910, OSHA General Industry Standards. Available from the U.S. Government Printing Office, Washington, DC 20402.
A11.2 Electrical Hazards. Electric shock can kill. However, it can be avoided. Live electrical parts should not be touched. The manufacturer’s instructions and recommended safety practices should be read and under- stood. Faulty installation, improper grounding, and in- correct operation and maintenance of electrical equip- ment are all sources of danger. All electrical equipment and the workpieces should be grounded. The workpiece lead is not a ground lead. It is used only to complete the welding circuit. A separate connection is required to ground the workpiece.
PART C — SPECIFICATIONS FOR WELDING RODS, ELECTRODES, AND FILLER METALS SFA-5.
A11.4.2 Nonionizing Radiation. The intensity and wavelengths of nonionizing radiant energy produced depend on many factors, such as the process, welding parameters, electrode and base-metal composition, fluxes, and any coating or plating on the base metal. Some processes, such as resistance welding, and cold pressure welding ordinarily produce negligible quantities of radiant energy. However, most arc welding and cutting processes (except submerged arc when used properly), laser beam welding and torch welding, cut- ting, brazing, or soldering can produce quantities of nonionizing radiation such that precautionary measures are necessary. Protection from possible harmful effects caused by nonionizing radiant energy from welding include the following measures: (a) One should not look at welding arcs except through filter plates which meet the requirements of ANSI/ASC Z87.1, Practice for Occupational and Edu- cational Eye and Face Protection , published by the American National Standards Institute. Transparent welding curtains are not intended as welding filter plates, but rather are intended to protect passersby from incidental exposure. (b) Exposed skin should be protected with adequate gloves and clothing as specified in ANSI/ASC Z49.1, Safety in Welding, Cutting, and Allied Processes , pub- lished by the American Welding Society. (c) Reflections from welding arcs should be avoided, and all personnel should be protected from intense reflections. ( Note: Paints using pigments of substantially zinc oxide or titanium dioxide have a lower reflectance for ultraviolet radiation. ) (d) Screens, curtains, or adequate distance from aisles, walkways, etc., should be used to avoid exposing passersby to welding operations. (e) Safety glasses with UV-protective side shields provide some beneficial protection from ultraviolet radi- ation produced by welding arcs.
A11.4.3 Ionizing radiation information sources include the following:
(a) ANSI/AWS F2.1-78, Recommended Safe Prac- tices for Electron Beam Welding and Cutting , available from the American Welding Society. (b) Manufacturer’s product information literature. A11.4.4 The following include nonionizing radia- tion information sources: (a) American National Standards Institute. ANSI/ ASC Z136.1, Safe Use of Lasers, New York, NY: American National Standards Institute. (b) ————. ANSI/ASC Z87.1, Practice for Occu- pational and Educational Eye and Face Protection. New York, NY: American National Standards Institute. (c) ————. ANSI/ASC Z49.1, Safety in Welding, Cutting, and Allied Processes : American Welding So- ciety. (d) Hinrichs, J. F. ‘‘Project Committee on Radia- tion—Summary Report.’’ Welding Journal , January
(e) Moss, C. E. ‘‘Optical Radiation Transmission Levels through Transparent Welding Curtains.’’ Welding Journal , March 1979. (f) Moss, C. E., and Murray, W. E. ‘‘Optical Radia- tion Levels Produced in Gas Welding, Torch Brazing, and Oxygen Cutting.’’ Welding Journal , September
(g) Marshall, W. J., Sliney, D. H., et al. ‘‘Optical Radiation Levels Produced by Air-Carbon Arc Cutting Processes.’’ Welding Journal , March 1980. (h) National Technical Information Service. Nonion- izing radiation protection special study No. 42-0053- 77, Evaluation of the Potential Hazards from Actinic Ultraviolet Radiation Generated by Electric Welding and Cutting Arcs. Springfield, VA: National Technical Information Service. ADA-033768. (i) National Technical Information Service. Nonion- izing radiation protection special study No. 42-0312- 77, Evaluation of the Potential Retina Hazards from Optical Radiation Generated by Electrical Welding and Cutting Arcs. Springfield, VA: National Technical Information Service. ADA-043023.
