AWS F3.2:2018

An American National Standard

Ventilation Guide for Weld Fume

AWS F3.2:2018

An American National Standard

Approved by the American National Standards Institute

December 14, 2017

Ventilation Guide for Weld Fume

2nd Edition

Supersedes AWS F3.2M/F3.2:2001

Prepared by the American Welding Society (AWS) Project Committee on Fumes and Gases

Under the Direction of the AWS Committee on Safety and Health

Approved by the AWS Board of Directors

Abstract

This document introduces the reader to various types of ventilation systems, including general supply and exhaust and local exhaust, for control of weld fumes. It contains or refers to information on air contaminants found in welding fumes, principles of system design and selection, and drawings that illustrate ventilation techniques.

ISBN: 978-0-87171-944-7

© 2018 by American Welding Society

All rights reserved Printed in the United States of America

Photocopy Rights. No portion of this standard may be reproduced, stored in a retrieval system, or transmitted in any form, including mechanical, photocopying, recording, or otherwise, without the prior written permission of the copyright owner.

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 provided that the appropriate fee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, tel: (978) 750-8400; Internet:

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Statement on the Use of American Welding Society Standards

All standards (codes, specifications, recommended practices, methods, classifications, and guides) of the American Welding Society (AWS) are voluntary consensus standards that have been developed in accordance with the rules of the American National Standards Institute (ANSI). When AWS American National Standards are either incorporated in, or made part of, documents that are included in federal or state laws and regulations, or the regulations of other governmental bodies, their provisions carry the full legal authority of the statute. In such cases, any changes in those AWS standards must be approved by the governmental body having statutory jurisdiction before they can become a part of those laws and regulations. In all cases, these standards carry the full legal authority of the contract or other document that invokes the AWS standards. Where this contractual relationship exists, changes in or deviations from requirements of an AWS standard must be by agreement between the contracting parties.

AWS American National Standards are developed through a consensus standards development process that brings together volunteers representing varied viewpoints and interests to achieve consensus. While AWS administers the process and establishes rules to promote fairness in the development of consensus, it does not independently test, evaluate, or verify the accuracy of any information or the soundness of any judgments contained in its standards.

AWS disclaims liability for any injury to persons or to property, or other damages of any nature whatsoever, whether special, indirect, consequential, or compensatory, directly or indirectly resulting from the publication, use of, or reliance on this standard. AWS also makes no guarantee or warranty as to the accuracy or completeness of any information published herein.

In issuing and making this standard available, AWS is neither undertaking to render professional or other services for or on behalf of any person or entity, nor is AWS undertaking to perform any duty owed by any person or entity to someone else. Anyone using these documents should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable care in any given circumstances. It is assumed that the use of this standard and its provisions is entrusted to appropriately qualified and competent personnel.

This standard may be superseded by new editions. This standard may also be corrected through publication of amendments or errata, or supplemented by publication of addenda. Information on the latest editions of AWS standards including amendments, errata, and addenda is posted on the AWS web page (www.aws.org). Users should ensure that they have the latest edition, amendments, errata, and addenda.

Publication of this standard does not authorize infringement of any patent or trade name. Users of this standard accept any and all liabilities for infringement of any patent or trade name items. AWS disclaims liability for the infringement of any patent or product trade name resulting from the use of this standard.

AWS does not monitor, police, or enforce compliance with this standard, nor does it have the power to do so.

Official interpretations of any of the technical requirements of this standard may only be obtained by sending a request, in writing, to the appropriate technical committee. Such requests should be addressed to the American Welding Society, Attention: Managing Director, Standards Development, 8669 NW 36 St, # 130, Miami, FL 33166 (see Annex B). With regard to technical inquiries made concerning AWS standards, oral opinions on AWS standards may be rendered. These opinions are offered solely as a convenience to users of this standard, and they do not constitute professional advice. Such opinions represent only the personal opinions of the particular individuals giving them. These individuals do not speak on behalf of AWS, nor do these oral opinions constitute official or unofficial opinions or interpretations of AWS. In addition, oral opinions are informal and should not be used as a substitute for an official interpretation.

This standard is subject to revision at any time by the AWS D10 Committee on Piping and Tubing. It must be reviewed every five years, and if not revised, it must be either reaffirmed or withdrawn. Comments (recommendations, additions, or deletions) and any pertinent data that may be of use in improving this standard are required and should be addressed to AWS Headquarters. Such comments will receive careful consideration by the AWS D10 Committee on Piping and Tubing and the author of the comments will be informed of the Committee’s response to the comments. Guests are invited to attend all meetings of the AWS D10 Committee on Piping and Tubing to express their comments verbally. Procedures for appeal of an adverse decision concerning all such comments are provided in the Rules of Operation of the Technical Activities Committee. A copy of these Rules can be obtained from the American Welding Society, 8669 NW 36 St,

# 130, Miami, FL 33166.

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Personnel

AWS Safety and Health Committee

D. E. Clark, Chair Consultant

D. Werba, Vice Chair Miller Electric Manufacturing Company

1. P. Hedrick, Secretary American Welding Society

   S. R. Fiore Hobart Brothers Company

   S. L. Foxworth ESAB Welding and Cutting Products

   M. Haaksma Orange County Ironworks, LLC

   K. A. Lyttle Consultant

   A. F. Manz A. F. Manz Associates

   1. M. Merlo-Joseph Apeks Supercritical

      J. Petkovsek The Lincoln Electric Company

      1. M Santasiero NJCTTC

      2. Solomon Extruflex North America

         
         

         Advisors to the Safety and Health Committee

      3. M. Donovan Sheet Metal Workers Local #265

         S. E. Ferree Consultant

         D. A. Fink The Lincoln Electric Company

         1. G. Harvey Hobart Brothers

            1. Hudson Hobart Brothers Company

1. D. Jennings Expert Services

   T. Lyon Consultant

   D. H. Sliney Consultant

   1. J. Tucker Consultant

      
      

      AWS Subcommittee on Fumes and Gases

2. A. Lyttle, Chair Consultant

1. R. Fiore, Vice Chair Hobart Brothers Company

1. P. Hedrick, Secretary American Welding Society

   D. N. Dunbar The Lincoln Electric Company

   D. A. Fink The Lincoln Electric Company

   1. L. Foxworth ESAB Welding and Cutting Products

      1. Hilbert Miller Electric Manufacturing Company

1. Hutchins Ohio BWC/Safety and Hygiene

   M. Merlo RevWires LLC

2. M. Merlo-Joseph Apeks Supercritical

J. J. Palach Pal-Tech Consulting Services

J. Petkovsek The Lincoln Electric Company

T. P. Rosiek Plymovent Corporation

Advisors to the Subcommittee on Fumes and Gases

M. Amata Hobart Brothers Company

H. R. Castner Edison Welding Institute

D. E. Clark Consultant

W. H. Drake S. W. Missouri State University

T. J. Eckardt Select-Arc Incorporated

S. E. Ferree Consultant

Foreword

This foreword is not part of this standard but is included for informational purposes only.

In 1981, the American Welding Society entered into an informal arrangement to distribute an insurance company publi- cation, Welding Fume Control with Mechanical Ventilation. In October 1986, the copyright was purchased and an updated version was prepared for publication as ANSI/AWS F3.1:1989, Guide for Welding Fume Control. It contained information to help plan new or evaluate existing systems for control of welding fume in the workplace. Because more than a revision was determined to be necessary, ANSI/AWS F3.1:1989 was withdrawn in 1997 and replaced with an updated and expanded ventilation guide, AWS F3.2: 2001. This revision is the second edition of F3.2. The health infor- mation listed for welding contaminants in the first edition have been removed and an expanded description of occupa- tional exposure limits was added. New clauses on Maintenance (Clause 9) and Confined Spaces (Clause 10) were added. The last edition of this document used dual dimensions, the International System of Units (SI) followed by U.S. Custom- ary Units in brackets and was designated F3.2M/F3.2. This edition uses U.S. Customary Units with approximate SI equivalents in parentheses, and is designated F3.2. This change was made because ventilation calculations in the U.S. are primarily in U.S. Customary Units.

Comments and suggestions for the improvement of this standard are welcome. They should be sent to the Secretary, Safety and Health Committee, American Welding Society, 8669 NW 36 St, # 130, Miami, FL 33166.

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Table of Contents

Page No.

Personnel v

Foreword vii

List of Tables xi

List of Figures xi

1. Introduction, Scope, and General Provisions 1

   1. Introduction 1

   2. Scope 1

   3. Units of Measure 1

   4. Safety 1

2. Normative References 2

3. Terms and Definitions 2

4. Occupational Exposure Limits 2

   1. Permissible Exposure Limits 2

   2. Threshold Limit Values 2

   3. Periodic Assessment 3

5. Ventilation 3

   1. Principles of Ventilation 3

   2. Local Exhaust Ventilation. 4

   3. General Ventilation 5

6. Types of Filtration 13

   1. Collector Selection 13

   2. Cartridge Collectors. 13

   3. Electrostatic Precipitators 15

   4. Fabric Collectors 15

   5. Fiberglass/Synthetic Multi-Pocket Filters 16

   6. Fire Precautions 16

   7. Safe Handling and Disposal of Collectors 17

7. Duct Design 17

8. Ventilation System Design Cases 17

   1. Natural Ventilation. 17

   2. Mechanical Ventilation 19

   3. General Ventilation Supply and Exhaust 19

   4. Local Exhaust and Recirculation 19

   5. Local Exhaust without Recirculation 21

   6. Local Exhaust Combined with General Exhaust without Recirculation 21

   7. Local High-Vacuum Exhaust System Combined with General Supply and Exhaust

      without Recirculation 22

9. Confined Spaces 23

   Page No.

10. Maintenance 24

Annex A (Informative)—References 25

Annex B (Informative)—Requesting an Official Interpretation on an AWS Standard 27

List of AWS Documents on Safety and Health 29

List of Tables

Table Page No.

1. Local Exhaust Ventilation 4

2. Local Ventilation Systems for Welding and Cutting Processes 5

3. Ventilation Selection Chart 18

List of Figures

Figure Page No.

1. Welding Gun with Integral Fume Extraction 6

2. High-Vacuum Source Capture Nozzle 6

3. Flexible Extraction Arms 7

4. Cross-Draft Welding Table with Slotted Hood 7

5. Fixed Exhaust Hood 8

6. Push-Pull Hood over Welding Robot 8

7. Canopy Hood 9

8. Downdraft Cutting Table 9

9. Methods of Air Distribution 12

10. Typical Cartridge Collector 14

11. Typical Portable Collector 14

12. Typical Electrostatic Precipitator 15

13. Typical Fabric Collector 16

14. Illustration of Natural Ventilation 18

15. Illustration of General Ventilation Supply and Exhaust 20

16. Illustration of Local Exhaust and Recirculation 20

17. Illustration of Local Exhaust without Recirculation 21

18. Illustration of Local Exhaust Combined with General Exhaust without Recirculation 22

19. Illustration of Local High-Vacuum Exhaust System Combined with General Supply and

Exhaust Systems without Recirculation 23

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Ventilation Guide for Weld Fume

1. Introduction, Scope, and General Provisions

   1. Introduction. A ventilation system consists of either a naturally, or mechanically, supplied and exhausted flow of air which can be used to control fumes and gases generated during welding or cutting operations. Mechanical ventilation systems are typically more consistent in their ability to control contaminants and are generally utilized when it is neces- sary to:

      1. Control contaminants to meet occupational exposure limits (PEL, TLV, etc.);

      2. Advance environmental stewardship by collecting emissions at the source, for disposal and recycle; and

      3. Improve housekeeping by reducing settled particulates.

   2. Scope. This guide describes recommended principles of ventilation to be used in facilities where welding and allied processes are performed. The primary objective of this document is to enhance the health and safety of all those found in a welding environment. Other objectives include the provision of information relevant to energy conservation and envi- ronmental compliance. This guide does not provide information on respiratory protection or specific precautions related to working in a confined space. Also, this guide does not address issues associated with combustible dust hazards appli- cable to ventilation systems. Information dealing with this issue can be found in NFPA 654, Standard for Prevention of Fire and Dust Explosions from the Manufacturing, Processing and Handling of Combustible Particulate Solids, and NFPA 484, Standard for Combustible Metals.

      Basic information related to a range of ventilation systems and techniques that can be used in a welding and cutting envi- ronment is provided here. Comparisons are drawn between techniques and highlight both the effectiveness and relative cost of each approach. It is intended that this information will assist in the identification and selection of an appropriate ventilation solution for a specific welding and/or cutting operation.

   3. Units of Measure. This standard makes sole use of U.S. Customary Units. Approximate mathematical equivalents in the International System of Units (SI) are provided for comparison in parentheses or in appropriate columns in tables and figures.

   4. Safety. Safety and health issues and concerns are beyond the scope of this standard; some safety and health informa- tion is provided, but such issues are not fully addressed herein.

      Sources of safety and health information include: American Welding Society:

      1. ANSI Z49.1, Safety in Welding, Cutting, and Allied Processes

      2. AWS Safety and Health Fact Sheets

      3. Other safety and health information on the AWS website Material or Equipment Manufacturers:

1. Safety Data Sheets (SDS) supplied by materials manufacturers

2. Operating Manuals supplied by equipment manufacturers Applicable regulatory agencies, such as:

1. Occupational Safety and Health Administration

2. Environmental Protection Agency