ANSI Z49.1:2005

An American National Standard

Safety in Welding, Cutting, and Allied Processes

Key Words—Welding safety and health,

cutting, welding fumes, hazard communication, fire prevention, respirators, electric shock, eye protection, noise

ANSI Z49.1:2005

An American National Standard

Approved by American National Standards Institute

July 15, 2005

Safety in Welding, Cutting, and Allied Processes

Supersedes ANSI Z49.1:1999

Prepared by Accredited Standards Committee Z49, Safety in Welding and Cutting

Secretariat American Welding Society

Abstract

This standard covers all aspects of safety and health in the welding environment, emphasizing oxygen gas and arc welding processes with some coverage given to resistance welding. It contains information on protection of personnel and the general area, ventilation, fire prevention and protection, and confined spaces. A significant section is devoted to precautionary information, showing examples, and an extensive bibliography is included.

550 N.W. LeJeune Road, Miami, Florida 33126

American National Standard

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CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be taken periodically to reaffirm, revise, or withdraw this standard. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute.

International Standard Book Number: 0-87171-023-4 American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126

© 2005 by American Welding Society. All rights reserved

Printed in the United States of America

Photocopy Rights

Authorization to photocopy items for internal, personal, or educational classroom use only, or the internal, personal, or educational classroom use only of specific clients, is granted by the American Welding Society (AWS) provided that the appropriate fee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, Tel: 978-750- 8400; online: https://www.copyright.com

Personnel

(The following is the roster of the Committee at the time of final committee action on the document.)

American National Standard Committee Z49

A. F. Manz, Chair

S. P. Hedrick, Secretary

ALLIANCE OF AMERICAN INSURERS

M. D. Ramsey

AMERICAN FOUNDRY SOCIETY

1. H. Kohloff

2. E. Mosher (Alternate)

AMERICAN OCCUPATIONAL MEDICAL ASSOCIATION

R. Blanchar, MD

AMERICAN PUBLIC HEALTH ASSOCIATION

E. Landau

AMERICAN SOCIETY OF SAFETY ENGINEERS

E. R. Ziegler

T. J. Martin (Alternate)

AMERICAN WELDING SOCIETY

S. R. Fiore

S. P. Hedrick (Alternate)

CANADIAN STANDARDS ASSOCIATION

J. J. Palach

CANADIAN WELDING BUREAU

J. MacRae

COMPRESSED GAS ASSOCIATION

A. F. Manz

R. A. Smith (Alternate)

INTERNATIONAL SAFETY EQUIPMENT ASSOCIATION, INCORPORATED

J. C. Bradley

MECHANICAL CONTRACTORS ASSOCIATION OF AMERICA, INCORPORATED

P. Chaney

W. Sperko

NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION, INCORPORATED

1. Stupczy

2. Winchester (Alternate)

NATIONAL FIRE PROTECTION ASSOCIATION

A. B. Spencer

T. C. Lemoff (Alternate)

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SHEET METAL WORKERS INTERNATIONAL

G. Batykefer

U.S. DEPARTMENT OF THE AIR FORCE

T. Pazell

1. G. Cox (Alternate)

   U.S. DEPARTMENT OF THE ARMY

2. C. Graham

U.S. DEPARTMENT OF LABOR

R. B. Bell (Nonvoting)

T. P. Smith (Nonvoting)

U.S. DEPARTMENT OF THE NAVY

J. E. Hernandez

J. Bishop (Alternate)

1. PUBLIC HEALTH SERVICE (NIOSH)

   A. Zimmer

   
   

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   Foreword

   
   

   (This Foreword is not a part of ANSI Z49.1:2005, Safety in Welding, Cutting, and Allied Processes, but is included for informational purposes only.)

   
   

   The huge demands for production placed on the United States by World War II brought a tremendous expansion to the use of welding. In mid 1943, it was recognized that some type of code or standard was needed relating to safe practices for performing welding. Under the auspices of the American Standards Association, the standard was drafted and published in 1944. It was entitled American War Standard Z49.1, Safety in Electric and Gas Welding, and Cutting Operations.

   Following the war, the standard was first revised in 1950. Subsequent revisions occurred in 1958, 1967, 1973, and 1983. Each updated the standard in accordance with changing technology and welding practices. The revisions up to and including 1973 were largely evolutionary and closely preserved the format of the original war standard.

   In 1983, a major rewrite was undertaken to take proper account of the vast changes in welding which had occurred in the 40 years of the standard's existence and to clarify the somewhat patchwork presentation that had built up during the evolutionary revisions. The scope was redefined to address in greater detail the safety rules to be practiced by the welder and enforced by welding supervision and management. Provisions which had appeared in earlier editions, but which dealt more with building construction and piping installation over which the welder had little control, were deleted. The 1988, 1994, 1999, and 2005 revisions follow this same philosophy.

   During the period of its publication, the American Standards Association has become the American National Stan- dards Institute and War Standard ASA Z49.1-1944 has now become ANSI Z49.1:2005.

   
   

   SUGGESTIONS

   Comments and suggestions for the improvement of this standard are welcome. They should be sent to the Secretary, Z49 Committee, American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126.

   
   

   REQUESTS FOR STANDARD INTERPRETATION

   Official interpretations of any of the technical requirements of this standard may be obtained by sending a request, in writing, to:

   Managing Director, Technical Services American Welding Society

   550 N.W. LeJeune Road Miami, FL 33126

   Requests not in writing cannot be considered for an official interpretation (see Annex E).

   
   

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   This page is intentionally blank.

   
   

   vi

   
   

   Table of Contents

   
   

   Page No.

   Personnel iii

   Foreword v

   List of Tables x

   List of Figures x

   Part I—General Aspects 1

   1. Purpose and Scope 1

      1. Purpose 1

      2. Scope and Applicability 1

      3. Exclusions 2

   2. Definitions 2

      1. Approved 2

      2. Confined Space 2

      3. Cylinder Storage 2

      4. Immediately Dangerous to Life or Health (IDLH) 3

      5. Other Definitions 3

      6. Qualified Person 3

      7. Shall 3

      8. Should 3

      9. Unit 3

      10. Welder. 3

   3. General Provisions, Management, and Supervision 3

      1. Setup and Installation 3

      2. Responsibilities 3

   4. Protection of Personnel and the General Area 5

      1. Protection of the General Area 5

      2. Eye and Face Protection 6

      3. Protective Clothing 9

      4. Noise Control 10

      5. Respiratory Protective Equipment 10

      6. Training. 10

   5. Ventilation 10

      1. General 10

      2. Breathing Zone Sampling 11

      3. Avoid the Fume 11

      4. Types of Ventilation 12

      5. Special Ventilation Concerns 12

   6. Fire Prevention and Protection 14

      1. Areas Containing Combustibles 14

      2. Fire Protection 15

      3. Hot-Work Authorization 16

      4. Welding or Cutting Containers 16

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         Page No.

   7. Confined Spaces 16

      1. Ventilation in Confined Spaces 16

      2. Location of Service Equipment 17

      3. Adjacent Areas 18

      4. Emergency Signal 18

      5. Attendants in Areas Immediately Dangerous to Life or Health (IDLH) 18

      6. Brazing Furnaces 18

   8. Public Exhibitions and Demonstrations 19

      1. Application 19

      2. Supervision 19

      3. Site 19

      4. Fire Protection 19

      5. Protection of the Public 19

      6. Cylinders 20

      7. Process Hoses, Cables, and Conduits 20

   9. Precautionary Information 20

      1. General 20

      2. Precautionary Information for Arc Welding and Related Processes and Equipment 21

      3. Precautionary Information for Oxyfuel Gas Processes and Equipment 21

      4. Hazardous Materials Information 22

      5. Brazing Filler Metals Containing Cadmium 22

      6. Brazing and Gas Welding Fluxes Containing Fluorides 22

      7. Material Safety Data Sheets (MSDSs) 22

      8. Graphic Symbols 22

      9. Hazard Communications 22

         Part II—Specific Processes 23

   10. Oxyfuel Gas Welding and Cutting Safety 23

       1. Scope. 24

       2. Terminology 24

       3. Oxygen and Combustibles 24

       4. Attachments for Gas Mixing 24

       5. Torches 24

       6. Hose and Hose Connections 25

       7. Pressure-Reducing Regulators 26

       8. Compressed and Oxyfuel Gas Cylinders (Containers) 26

       9. Cylinder Manifolding 31

   11. Arc Welding and Cutting Equipment Safety 32

       1. General 32

       2. Safety Aspects in Selection of Arc Welding Equipment 32

       3. Installation of Arc Welding Equipment 33

       4. Operation 36

       5. Maintenance 38

   12. Resistance Welding Safety 39

       1. General 39

       2. Installation 40

       3. Guarding 40

       4. Electrical 41

       5. Static Safety Devices 42

       6. Ventilation 42

       7. Maintenance 42

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          Page No.

   13. Electron Beam Welding and Cutting Processes (EBW and EBC) 43

       1. General 43

       2. Potential Hazards 43

   14. Laser Beam Cutting and Welding 44

       1. General 44

   15. Brazing and Soldering Safety 44

       1. General 44

       2. Potential Hazards 44

Nonmandatory Annexes 47

Annex A—American Welding Society Safety and Health Standards List 47

Annex B—List of Other Sources 49

Annex C—List of Publishers 51

Annex D—Master Chart of Welding and Joining Processes and Master Chart of Allied Processes 53

Annex E—Guidelines for Preparation of Technical Inquiries for the Z49 Committee 55

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List of Tables

Table Page No.

1 Guide for Shade Numbers 7

List of Figures

Figure Page No.

1. Precautionary Information for Arc Welding Processes and Equipment 21

2. Precautionary Information for Oxyfuel Gas Processes and Equipment 21

3. Precautionary Information for Brazing Filler Metals Containing Cadmium 23

4. Precautionary Information for Brazing and Gas Welding Fluxes Containing Fluorides 23

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Safety in Welding, Cutting, and Allied Processes

(American National Standard Z49.1:2005 uses a two-column format to provide both specific requirements and supporting information. The left column is designated as “Standard Requirements” and the right column is designated as “Explana- tory Information.” The paragraph number of the Explanatory Information is preceded by the letter “E.”)

Standard Requirements Explanatory Information

Part I General Aspects

1. Purpose and Scope

   1. Purpose. This standard is for the protection of per- sons from injury and illness and the protection of property (including equipment) from damage by fire and explosions arising from welding, cutting, and allied processes.

      
      

   2. Scope and Applicability. This standard shall be for the guidance of educators, operators, managers, and super- visors in the safe setup and use of welding and cutting equipment, and the safe performance of welding and cut- ting operations.

      
      

      E1.1 Beginning with the revision of 1983, the scope of ANSI Standard Z49.1 has been refocused towards those safe practices for performing welding, cutting, and allied processes, which are generally within the implementation control of the welder or the weld shop management. It is written in a manner suitable for issuance to the welder and shop management to give practical information to help them perform these functions safely. It also contains in- formation useful to educators, industrial hygienists, engi- neers, and similar parties also responsible for safety and health in welding. With this refocused scope, some provi- sions which appeared in prior editions have been deleted. Those were provisions which dealt more in matter of build- ing design and construction, facility pipelines, and electri- cal installations. Those provisions, of course, are still important and necessary and must be followed. They are not provisions usually under the immediate control of welding and cutting operations.

      E1.2 Specific provisions are included for oxyfuel gas and arc welding and cutting, resistance welding, electron beam welding, laser beam cutting and welding, and brazing and soldering.

      However, the requirements of this standard are gener- ally applicable to the other welding processes such as submerged arc welding and allied processes shown in the American Welding Society Master Chart of Welding and Allied Processes, included in Annex D.

      
      

      
      

      1

   3. Exclusions. This standard shall not pertain to the following:

      1. Guidelines for the design or manufacture of equipment

      2. Building piping systems

      3. Pipeline protection systems and station outlet equipment

      4. Bulk gas supply systems

      5. Building electrical installations.

         E1.3 Some of these were included in former issues of the standard. These items were eliminated from ANSI Z49.1 to avoid their being included in two separate standards under separate auspices which can lead to conflict or confusion between standards.

         These are contained in standards and codes of the National Fire Protection Association (NFPA) as follows:

         1. Oxyfuel gas piping systems, pipeline protective devices, and station outlet equipment—ANSI/NFPA 51, Standard for the Design and Installation of Oxygen-Fuel Gas Systems for Welding, Cutting, and Allied Processes

         2. Storage and manifolding of multiple gas cylin- ders—ANSI/NFPA 51

         3. Acetylene generators and calcium carbide storage—

            ANSI/NFPA 51

         4. Bulk oxygen systems—ANSI/NFPA 50, Standard for Bulk Oxygen Systems at Consumer Sites

         5. Bulk LP-Gas and MPS systems—ANSI/NFPA 58,

            Storage and Handling of Liquefied Petroleum Gases

         6. Building electrical installations—ANSI/NFPA 70,

            National Electrical Code®

         7. Industrial machinery—ANSI/NFPA 79, Electrical Standard for Industrial Machinery.

         
         

2. Definitions

   The following definitions shall apply to this standard.

   1. Approved. Approved and approval as used in this standard mean acceptable to the authority having jurisdiction.

1. Authority Having Jurisdiction. This term refers to the organization, office, or individual responsible for “approving” equipment, an installation, or a procedure.

2. Listed. This term means the equipment or mate- rial included in a list published by a nationally recognized testing laboratory that maintains periodic inspection of production of listed equipment or materials.

1. Confined Space. Refers to a relatively small or restricted space such as a tank, boiler, pressure vessel, or small compartment. Confinement implies poor ventilation as a result of construction, size, or shape rather than restriction of egress of personnel.

2. Cylinder Storage. Refers to cylinders of compressed gas standing by on the site (not those in use or attached ready for use).

2.3.1 Cylinders in Use. This term refers to the following:

1. Cylinders connected for use,

2. A single cylinder for each gas to be used, in the use location, ready to be connected, or

E2.2 For additional information, see ANSI Z117.1, Safety Requirements for Confined Spaces, or the pertaining OSHA standard.

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