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The Public Right-of-Way Accessibility Guidelines (PROWAG) rulemaking has concluded. The PROWAG final rule has been published in the Federal Register. Please visit the Access Board’s PROWAG page for the guidelines.

ADA Access to Passenger Vessels: Finding Safety Equivalence Solutions for Weathertight Doors with Coamings

March 2005people using power chairs board vessel

Prepared for: The U.S. Access Board

Prepared by:
U.S. Department of Transportation
Research and Innovative Technologies Administration
John A. Volpe National Transportation Systems Center
Cambridge, Massachusetts

Michael G. Dyer
NOTICE: Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or use of any information, apparatus, product, or process disclosed. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United State Government or any agency thereof.


This report examines a risk management methodology to provide for both marine safety and disability access at weathertight doors into passenger accommodation spaces on U.S. passenger vessels. The Architectural and Transportation Barriers Compliance Board’s ultimate objective is to assist designers and operators in improving disability access without compromising the vessel safety provisions of the coamings (sills) at these doorways. The methodology assigns numeric risk scores to several watertight integrity safety factors including door location and use, downflooding path, and vessel service. The aggregate risk score for a given door corresponds to a menu of possible access solutions. The methodology allows for the relocation of the door or other measures to lower the risk score and improve the access solution. The model is applied to several examples of doors on Subchapter T and K passenger boats.


The author wishes to thank the numerous organizations and individuals who graciously provided their time, knowledge and guidance in the development of this report. Our sponsors at the Architectural and Transportation Barriers Compliance Board have been supportive. We owe thanks to many in the U.S. Coast Guard who responded to our inquiries and contributed their time, their knowledge, and their experience. They include Captain Raymond Petow, Mr. Tom Jordan and Mr. Al Penn (Coast Guard Headquarters), LT Jason Hall and CWO4 Jim Hinde (Marine Safety Office, Boston), CWO Ray Rock (Marine Safety Office, Providence), and LCDR Tony Wiest (Marine Safety Center).

Several well-regarded naval architects contributed their knowledge and insight to review of the risk management methodology, affirming its credibility by a critical first review. Heartfelt gratitude is due Tim Graul of Timothy Graul Designs, John Hunter of Seaworthy Systems, and John Waterhouse of Elliott Bay Design Group. Pete Lauridsen of the Passenger Vessels Association (PVA) provided valuable technical guidance and was instrumental in setting up a peer review process by the PVA Partnership Action Team.

Finally, we must thank those who contributed the boat designs used as examples demonstrating application of the methodology. They were:

  • Casco Bay Line and Seaworthy Systems;
  • Timothy Graul Designs; and
  • Gladding-Hearn Shipbuilding, Duclos Corporation and INCAT Designs


ADA - Americans with Disabilities Act, 1990
ADAAG - ADA Accessibility Guidelines for Buildings and Facilities (2002)
ATBCB - Architectural and Transportation Barriers Compliance Board
CFR - Code of Federal Regulations
COI - Certificate of Inspection
COTP -Captain of the Port
DOT - U.S. Department of Transportation
DF - Downflooding
ILLC -International Load Line Convention
IMO - International Maritime Organization
LLTM - Load Line Technical Manual
NVIC - Navigation and Vessel Inspection Circular
OCMI - Officer in Charge of Marine Inspection
PAT - Partnership Action Team
PAX - Passengers
PVA - Passengers Vessels Association
PVAAC - Passenger Vessel Access Advisory Committee
WL - Waterline