ANSI Z49.1:2012

An American National Standard

Safety in Welding, Cutting, and Allied Processes

ANSI Z49.1:2012

An American National Standard

Approved by the American National Standards Institute

March 9, 2012

Safety in Welding, Cutting, and Allied Processes

Supersedes ANSI Z49.1:2005

Prepared by the 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.

American National Standard

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International Standard Book Number: 978-0-87171-809-9

American Welding Society 550 N.W. LeJeune Road, Miami, FL 33126

© 2012 by American Welding Society

All rights reserved Printed in the United States of America

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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, Chairman

S. P. Hedrick, Secretary

AMERICAN FOUNDRY SOCIETY

F. H. Kohloff

AMERICAN COLLEGE OF OCCUPATIONAL AND ENVIRONMENTAL MEDICINE

L. Lee

W. Milliken (Alternate)

E. Favata (Alternate)

AMERICAN PUBLIC HEALTH ASSOCIATION

N. Tristani

AMERICAN SOCIETY OF SAFETY ENGINEERS

E. R. Ziegler

T. J. Martin (Alternate)

AMERICAN WELDING SOCIETY

D. Clark

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 ASSOCIATION OF BRIDGE, STRUCTURAL, ORNAMENTAL AND REIFORCING IRON WORKERS

E. Abbott

INTERNATIONAL THERMAL SPRAY ASSOCIATION

D. Hayden

INTERNATIONAL SAFETY EQUIPMENT ASSOCIATION, INCORPORATED

J. Franklin

C. Fargo

MECHANICAL CONTRACTORS ASSOCIATION OF AMERICA, INCORPORATED

P. Chaney

W. Sperko

NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION, INCORPORATED

1. Stupczy

2. Winchester (Alternate)

NATIONAL FIRE PROTECTION ASSOCIATION

D. Duval

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

R. Wright

U.S. DEPARTMENT OF LABOR

R. B. Bell (nonvoting)

U.S. DEPARTMENT OF THE NAVY

E. Berg

1. PUBLIC HEALTH SERVICE (NIOSH)

   M. Gressel

   
   

   Foreword

   
   

   This foreword is not part of ANSI Z49.1:2012, 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 pub- lished 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 evo- lutionary 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, 2005, and 2012 revisions follow this same philosophy. Revisions are identified by a vertical line in the mar- gin next to the text.

   During the period of its publication, the American Standards Association has become the American National Standards Institute and War Standard ASA Z49.1-1944 has now become ANSI Z49.1:2012.

   
   

   SUGGESTIONS

   Comments and suggestions for the improvement of this standard are welcome. They should be sent to the Secretary, ANSI 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).

   
   

   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 3

      3. Cylinder Storage 3

      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 4

   4. Protection of Personnel and the General Area 6

      1. Protection of the General Area 6

      2. Eye and Face Protection 6

      3. Protective Clothing 9

      4. Noise Control 10

      5. Respiratory Protective Equipment 10

      6. Training 11

   5. Ventilation 11

      1. General 11

      2. Breathing Zone Sampling 12

      3. Avoid the Fume 12

      4. Types of Ventilation 12

      5. Special Ventilation Concerns 13

   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

   7. Confined Spaces 17

      1. Ventilation in Confined Spaces 17

      2. Location of Service Equipment 18

      3. Adjacent Areas 18

      4. Emergency Signal 18

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

      6. Brazing Furnaces 19

   8. Public Exhibitions and Demonstrations 19

      1. Application 19

      2. Supervision 19

      3. Site 19

      4. Fire Protection 20

      5. Protection of the Public 20

      6. Cylinders 20

      7. Process Hoses, Cables, and Conduits 21

   9. Precautionary Information 21

      1. General 21

      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 21

      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 23

      9. Hazard Communications 23

         Part II—Specific Processes 24

   10. Oxyfuel Gas Welding and Cutting Safety 24

       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) 27

       9. Cylinder Manifolding 32

   11. Arc Welding and Cutting Equipment Safety 32

       1. General 32

       2. Safety Aspects in Selection of Arc Welding Equipment 33

       3. Installation of Arc Welding Equipment 34

       4. Operation 35

       5. Maintenance 38

   12. Resistance Welding Safety 39

       1. General 39

       2. Installation 40

       3. Guarding 40

       4. Electrical 41

       5. Static Safety Devices 43

       6. Ventilation 44

       7. Maintenance 44

   13. Electron Beam Welding and Cutting Processes (EBW and EBC) 44

       1. General 44

       2. Potential Hazards 44

   14. Laser Beam Cutting and Welding 45

       1. General 45

   15. Brazing and Soldering Safety 45

       1. General 45

       2. Potential Hazards 45

Annex A (Informative)—American Welding Society Safety and Health Standards List 49

Annex B (Informative)—List of Other Sources. 51

Annex C (Informative)—List of Publishers 53

Annex D (Informative)—Master Chart of Welding and Joining Processes and Master Chart of

Allied Processes 55

Annex E (Informative)—Guidelines for the Preparation of Technical Inquiries for the Z49 Committee 57

List of Tables

Table Page No.

1 Guide for Shade Numbers 8

List of Figures

Figure Page No.

1. Precautionary Information for Arc Welding Processes and Equipment 22

2. Precautionary Information for Oxyfuel Gas Processes and Equipment 22

3. Precautionary Information for Brazing Filler Metals Containing Cadmium 23

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

Safety in Welding, Cutting, and Allied Processes

(American National Standard Z49.1:2012 uses a two-column format to provide both specific requirements and sup- porting information. The left column is designated as “Standard Requirements” and the right column is designated as “Explanatory Information.” The paragraph number of the Explanatory Information is preceded by the letter “E.”)

Standard Requirements

Part I General Aspects

1. Purpose and Scope

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

      Explanatory Information

      
      

      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 information useful to educators, industrial hygienists, engineers, and similar parties also responsible for safety and health in welding. With this refocused scope, some provisions which appeared in prior editions have been deleted. Those were provisions which dealt more in matter of building design and construction, facility pipelines, and electrical 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.

      
      

   2. Scope and Applicability. This standard shall be for the guidance of educators, operators, managers, and supervisors in the safe setup and use of welding and cutting equipment, and the safe performance 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 generally applicable to the other welding processes such as sub- merged arc welding and allied processes shown in the American Welding Society Master Chart of Welding and Allied Processes, included in Annex D.