Safety Standard

for Pressure Vessels for Human Occupancy: In-Service Guidelines

AN A MERICAN NA TIONAL S T AND ARD

ASME PVHO-2–2016

(Revision of ASME PVHO-2–2012)

ASME PVHO-2–2016

(Revision of ASME PVHO-2–2012)

Safety Standard

for Pressure Vessels for Human Occupancy: In-Service Guidelines

AN AMERICAN NA TIONAL S T AND ARD

Two Park Avenue • New York, NY • 10016 USA

Date of Issuance: June 29, 2016

The next edition of this Standard is scheduled for publication in 2019.

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The American Society of Mechanical Engineers Two Park Avenue, New York, NY 10016-5990

Copyright © 2016 by

THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS

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CONTENTS

Foreword iv

Committee Roster v

Correspondence With the PVHO Committee viii

Summary of Changes ix

Mandatory Appendices

1. Definitions 23

2. Reference Standards and Specifications 25

3. Quality Assurance Program for Repair of Severely Damaged Windows 26

4. Additional Window Repair Requirements and Forms 29

5. Partial List of Harmful Substances and Acceptable Products 35

6. Mechanical Testing Computations and Forms 37

Nonmandatory Appendices

1. Checklists and Logs for PVHO Operation 41

2. Operation of Submersible Craft 42

FOREWORD

In 1998 a PVHO Task Group was formed to investigate the need for In-Service Rules and Guidelines for Pressure Vessels for Human Occupancy. Simultaneously, a Sub Task Group was formed to investigate the issue of acrylic window design life versus service life. The design life is based on the PVHO window being exposed to the maximum allowable working pressure (MAWP), at the maximum rated temperature, for the maximum number of (design) cycles, in an outdoor weathering environment. The majority of PVHOs are not operated to such extremes, and service life may indeed be longer than design life. Conversely, if a window is not properly cared for (i.e., becomes exposed, either operationally or nonoperationally, to other detrimental factors that are not, and cannot be, factored into the design life), then the actual service life could be much shorter than the design life. Thus, the recommendation was made that design life and service life be addressed as two different subjects. In 1999 the In-Service Task Group became a PVHO subcommittee, with the most immediate task being the establishment of in-service criteria for PVHO windows and viewports.

This Standard provides the necessary in-service criteria to supplement Section 2, Viewports, of ASME PVHO-1, which applies to new construction only. By comparison, this Standard applies to all PVHO-1 acrylic windows, regardless of their date of manufacture. This Standard consists of both Technical Criteria and Guidelines. They are intended to provide guidance to the User and/or the Jurisdictional Authority in regard to the establishment of potential Service Life, and the necessary care, inspection, and repair during that Service Life—depending on the actual service conditions to which the PVHO and windows have been, or will be, exposed.

Finally, this Standard was prepared as a “stand-alone” document. All Forms additional to those normally supplied with the window in accordance with PVHO-1, which may be necessary throughout the service life of the window, are provided herein. Similarly, all necessary PVHO-1 technical data applicable to service and repair (if required) are also provided in this Standard.

The 2016 Edition of PVHO-2 includes revisions to the in-service pressure testing and tempera- ture abuse factors’ requirements. It also includes an updated definition for “refurbishment” as well as two new Nonmandatory Appendices covering operation of submersible craft and checklists and logs intended for operation of PVHOs.

Previous editions of this Standard were issued in 2003 and 2012. The 2016 Edition of this Standard was approved by the American National Standards Institute as an American National Standard on January 6, 2016.

ASME PRESSURE VESSELS FOR HUMAN OCCUPANCY COMMITTEE

(The following is the roster of the Committee as of July 24, 2015.)

STANDARDS COMMITTEE OFFICERS

G. K. Wolfe, Chair

J. Witney, Vice Chair

G. E. Moino, Secretary

M. W. Allen, Microbaric Oxygen Systems LLC

J. E. Crouch, Southwest Research Institute

W. F. Crowley, Jr., Aerospace and Undersea

W. Davison, Oxyheal Health Group

B. Faircloth, FMS Engineering LLC

E. G. Fink, Fink Engineering, Ltd.

M. A. Frey, Naval Sea Systems Command

T. R. Galloway, Naval Sea Systems Command

G. P. Jacob, Navy Experimental Diving Unit

C. B. Kemper III, Kemper Engineering LLC

W. Kohnen, Hydrospace Group LLC

J. D. Lawrence, U.S. Coast Guard

P. A. Lewis, Hyperbaric Technologies, Inc.

STANDARDS COMMITTEE PERSONNEL

H. Pauli, DNV GL

J. P. Hierholzer, Alternate, DNV GL

S. D. Reimers, Reimers Systems, Inc.

G. Richards, Blanson, Ltd.

T. C. Schmidt, Lockheed Martin

J. S. Selby, S.O.S. Medical Group, Ltd.

P. Selby, Alternate, S.O.S. Medical Group, Ltd.

1. C. Sheffield, International ATMO, Inc.

2. A. Smith, U.S. Coast Guard

R. C. Smith, Naval Facilities Engineering Command, Ocean Facilities Program

D. Talati, Sechrist Industries, Inc.

R. Thomas, American Bureau of Shipping (ABS)

J. R. Maison, Adaptive Computer Technology, Inc.

T. T. Marohl, Consultant

G. E. Moino, The American Society of Mechanical Engineers

M. R. Walters, Oceaneering International, Inc.

J. Witney, Atlantis Submarines International

G. K. Wolfe, Southwest Research Institute

R. J. Dzikowski

F. T. Gorman

HONORARY MEMBERS

L. G. Malone

R. P. Swanson

T. C. Schmidt, Chair, Lockheed Martin

G. Richards, Vice Chair, Blanson, Ltd.

M. W. Allen, Microbaric Oxygen Systems LLC

F. Burman, DAN Southern Africa

W. F. Crowley, Jr., Aerospace and Undersea

W. Davison, Oxyheal Health Group

R. K. Dixit, Reimers Systems, Inc.

B. Faircloth, FMS Engineering LLC

SUBCOMMITTEE ON DESIGN AND PIPING

G. P. Jacob, Navy Experimental Diving Unit

C. B. Kemper III, Kemper Engineering Services LLC

K. A. Wohlfeil, Alternate, Kemper Engineering Services LLC

R. Kumar, Reimers Systems, Inc.

P. A. Lewis, Hyperbaric Technologies, Inc.

S. D. Reimers, Reimers Systems, Inc.

D. A. Renear, Aqua-Air Industries, Inc.

C. D. Johnstone, Alternate, Blanson, Ltd.

P. Forte, Woods Hole Oceanographic Institution

M. A. Frey, Naval Sea Systems Command

T. R. Galloway, Naval Sea Systems Command

R. M. Webb, Alternate, Naval Sea Systems Command

C. Gaumond, Medical Groupe Gaumond

B. Humberstone, Global Diving and Salvage

J. S. Selby, S.O.S. Medical Group, Ltd.

P. Selby, Alternate, S.O.S. Medical Group, Ltd.

R. Thomas, American Bureau of Shipping (ABS)

M. R. Walters, Oceaneering International, Inc.

J. Witney, Atlantis Submarines International

SUBCOMMITTEE ON DIVING SYSTEMS

T. R. Galloway, Chair, Naval Sea Systems Command

M. R. Walters, Vice Chair, Oceaneering International, Inc.

M. W. Allen, Microbaric Oxygen Systems LLC

W. F. Crowley, Jr., Aerospace and Undersea

W. Davison, Oxyheal Health Group

B. Faircloth, FMS Engineering LLC

E. G. Fink, Fink Engineering, Ltd.

1. Humberstone, Global Diving and Salvage

2. B. Kemper III, Kemper Engineering Services LLC

K. A. Wohlfeil, Alternate, Kemper Engineering Services LLC

J. D. Lawrence, U.S. Coast Guard

T. Gilman, Alternate, U.S. Coast Guard

P. A. Lewis, Hyperbaric Technologies, Inc.

T. T. Marohl, Consultant

H. Pauli, DNV GL

D. A. Renear, Aqua-Air Industries, Inc.

J. S. Selby, S.O.S. Medical Group, Ltd.

P. Selby, Alternate, S.O.S. Medical Group, Ltd.

K. A. Smith, U.S. Coast Guard

R. Thomas, American Bureau of Shipping (ABS)

SUBCOMMITTEE ON GENERAL REQUIREMENTS

M. A. Frey, Chair, Naval Sea Systems Command

M. W. Allen, Vice Chair, Microbaric Oxygen Systems LLC

J. E. Crouch, Southwest Research Institute

T. R. Galloway, Naval Sea Systems Command

R. M. Webb, Alternate, Naval Sea Systems Command

G. P. Jacob, Navy Experimental Diving Unit

S. D. Reimers, Reimers Systems, Inc.

J. S. Selby, S.O.S. Medical Group, Ltd.

P. Selby, Alternate, S.O.S. Medical Group, Ltd.

G. K. Wolfe, Southwest Research Institute

SUBCOMMITTEE ON MEDICAL HYPERBARIC SYSTEMS

M. W. Allen, Chair, Microbaric Oxygen Systems LLC

W. Davison, Vice Chair, Oxyheal Health Group

T. Dingman, Healogics

K. W. Evans, Perry Baromedical

E. G. Fink, Fink Engineering, Ltd.

C. Foreman, U.S. Food and Drug Administration

W. T. Gurnee, Oxyheal Health Group

C. B. Kemper III, Kemper Engineering Services LLC

K. A. Wohlfeil, Alternate, Kemper Engineering Services LLC

P. A. Lewis, Hyperbaric Technologies, Inc.

H. Pauli, DNV GL

S. D. Reimers, Reimers Systems, Inc.

J. C. Sheffield, International ATMO, Inc.

D. Talati, Sechrist Industries, Inc.

SUBCOMMITTEE ON POST CONSTRUCTION

R. C. Smith, Chair, Naval Facilities Engineering Service Center

W. Davison, Vice Chair, Oxyheal Health Group

M. W. Allen, Microbaric Oxygen Systems LLC

J. E. Crouch, Southwest Research Institute

W. F. Crowley, Jr., Aerospace and Undersea

T. Dingman, Healogics

M. A. Frey, Naval Sea Systems Command

T. R. Galloway, Naval Sea Systems Command

R. M. Webb, Alternate, Naval Sea Systems Command

B. Humberstone, Global Diving and Salvage

G. P. Jacob, Navy Experimental Diving Unit

C. B. Kemper III, Kemper Engineering Services LLC

K. A. Wohlfeil, Alternate, Kemper Engineering Services LLC

J. D. Lawrence, U.S. Coast Guard

T. Gilman, Alternate, U.S. Coast Guard

G. Richards, Blanson, Ltd.

T. C. Schmidt, Lockheed Martin

J. C. Sheffield, International ATMO, Inc.

D. Talati, Sechrist Industries, Inc.

J. Witney, Atlantis Submarines International

J. Witney, Chair, Atlantis Submarines International

G. Richards, Vice Chair, Blanson, Ltd.

M. W. Allen, Microbaric Oxygen Systems LLC

P. Everley, Delegate, Stanley Plastics, Ltd.

1. Faircloth, FMS Engineering LLC

2. B. Kemper III, Kemper Engineering Services LLC

SUBCOMMITTEE ON VIEWPORTS

J. D. Lawrence, U.S. Coast Guard

T. Gilman, Alternate, U.S. Coast Guard

D. A. Renear, Aqua-Air Industries, Inc.

T. C. Schmidt, Lockheed Martin

R. C. Smith, Naval Facilities Engineering Service Center

1. Stromer, Triton Submarines

2. A. Wohlfeil, Alternate, Kemper Engineering Services LLC

W. Kohnen, Hydrospace Group LLC

D. Talati, Sechrist Industries, Inc.

R. Thomas, American Bureau of Shipping (ABS)

W. Kohnen, Chair, Hydrospace Group LLC

W. F. Crowley, Jr., Aerospace and Undersea

T. R. Galloway, Naval Sea Systems Command

SUBCOMMITTEE ON SUBMERSIBLES

T. C. Schmidt, Lockheed Martin

K. A. Smith, U.S. Coast Guard

J. D. Lawrence, Alternate, U.S. Coast Guard

R. M. Webb, Alternate, Naval Sea Systems Command

H. Pauli, DNV GL

R. Thomas, American Bureau of Shipping (ABS)

J. Witney, Atlantis Submarines International

CORRESPONDENCE WITH THE PVHO COMMITTEE

General. ASME Standards are developed and maintained with the intent to represent the consensus of concerned interests. As such, users of this Standard may interact with the Committee by requesting interpretations, proposing revisions or a Case, and attending Committee meetings. Correspondence should be addressed to:

Secretary, PVHO Standards Committee

The American Society of Mechanical Engineers Two Park Avenue

New York, NY 10016-5990

https://go.asme.org/Inquiry

Proposing Revisions. Revisions are made periodically to the Standard to incorporate changes that appear necessary or desirable, as demonstrated by the experience gained from the application of the Standard. Approved revisions will be published periodically.

The Committee welcomes proposals for revisions to this Standard. Such proposals should be as specific as possible, citing the paragraph number(s), the proposed wording, and a detailed description of the reasons for the proposal, including any pertinent documentation.

Proposing a Case. Cases may be issued for the purpose of providing alternative rules when justified, to permit early implementation of an approved revision when the need is urgent, or to provide rules not covered by existing provisions. Cases are effective immediately upon ASME approval and shall be posted on the ASME Committee Web page.

Requests for Cases shall provide a Statement of Need and Background Information. The request should identify the Standard and the paragraph, figure, or table number(s), and be written as a Question and Reply in the same format as existing Cases. Requests for Cases should also indicate the applicable edition(s) of the Standard to which the proposed Case applies.

Interpretations. Upon request, the PVHO Committee will render an interpretation of any requirement of the Standard. Interpretations can only be rendered in response to a written request sent to the Secretary of the PVHO Standards Committee.

The request for interpretation should be clear and unambiguous. It is further recommended that the inquirer submit his/her request in the following format:

Subject: Cite the applicable paragraph number(s) and the topic of the inquiry.

Edition: Cite the applicable edition of the Standard for which the interpretation is being requested.

Question: Phrase the question as a request for an interpretation of a specific requirement suitable for general understanding and use, not as a request for an approval of a proprietary design or situation. The inquirer may also include any plans or drawings that are necessary to explain the question; however, they should not contain proprietary names or information.

Requests that are not in this format may be rewritten in the appropriate format by the Committee prior to being answered, which may inadvertently change the intent of the original request.

ASME procedures provide for reconsideration of any interpretation when or if additional information that might affect an interpretation is available. Further, persons aggrieved by an interpretation may appeal to the cognizant ASME Committee or Subcommittee. ASME does not “approve,” “certify,” “rate,” or “endorse” any item, construction, proprietary device, or activity. Attending Committee Meetings. The PVHO Standards Committee regularly holds meetings and/or telephone conferences that are open to the public. Persons wishing to attend any meeting and/or telephone conference should contact the Secretary of the PVHO Standards Committee.

ASME PVHO-2–2016 SUMMARY OF CHANGES

Following approval by the PVHO Committee and ASME, and after public review, ASME PVHO-2–2016 was approved by the American National Standards Institute on January 6, 2016.

ASME PVHO-2-2016 includes the following changes identified by (16).

INTENTIONALLY LEFT BLANK

ASME PVHO-2–2016

SAFETY STANDARD FOR PRESSURE VESSELS FOR HUMAN OCCUPANCY: IN-SERVICE GUIDELINES

Section 1 General

1. INTRODUCTION AND SCOPE

   1. This Standard provides technical requirements and guidelines for the operation and maintenance of PVHOs and PVHO systems that were designed, con- structed, tested, and certified in accordance with ASME PVHO-1, Safety Standard for Pressure Vessels for Human Occupancy.

   2. This Standard provides technical criteria for the user to esta