NVIC 15-91: Modifying Critical Areas Inspection Plan requirements

NAVIGATION AND VESSEL INSPECTION CIRCULAR NO. 15-91, CH-1 Subj: CRITICAL AREA INSPECTION PLANS (CAIPs)

Critical Areas Inspection Plans (CAIPs) — PURPOSE. This Circular establishes the procedures by which owners and operators of vessels required to maintain CAIPs may apply to modify the scope and/or examination intervals established in their initial CAIP.

PURPOSE. This Circular establishes the procedures by which owners and operators of vessels required to maintain CAIPs may apply to modify the scope and/or examination intervals established in their initial CAIP.

Critical Areas Inspection Plans (CAIPs) — DIRECTIVES AFFECTED. NVIC 15-91, CAIPs, is amended to incorporate the policies and guidance provided, herein, concerning modifications to the scope and frequency of CAIP exams.

DIRECTIVES AFFECTED. NVIC 15-91, CAIPs, is amended to incorporate the policies and guidance provided, herein, concerning modifications to the scope and frequency of CAIP exams.

Critical Areas Inspection Plans (CAIPs) — BACKGROUND.

a. By the late 1980s, following a number of well publicized marine casualties, the Coast Guard began to focus attention on structural failures of ocean going vessels. The intent was to identify trends in the pattern of structural failures, and to develop recommendations by which to reduce the number and severity of such occurrences. b. On 27 April 1988, the Marine Inspection Program Casualty Review Council issued a report which identified Trans-Alaska Pipeline Service (TAPS) tankers as suffering a disproportionately higher number of structural failures compared to similar vessels in other areas. In early 1990, the Coast Guard contacted TAPS vessel operators to notify them of changes in inspection policies for these tankships, and to solicit information which the operators themselves had obtained concerning structural failures and their maintenance practices. c. The Coast Guard's "TAPS TANKER STRUCTURAL FAILURE STUDY" cited poorly designed structural details, poor weld workmanship, and fatigue, especially in association with the use of high strength steel, and the harsh environment of the Gulf of Alaska, as contributing causes of structural failures in TAPS vessels. d. The implementation of CAIPs was one of the significant outcomes from this study. Vessels which have experienced, or by virtue of class design and/or service and trade route could expect to experience structural failures, are required to develop CAIPs. As discussed in NVIC 15-91, CAIPs are a management tool developed by the vessel's owner or operator to document and track structural failures, and to monitor the performance of various repair methodologies.

Critical Areas Inspection Plans (CAIPs) — DISCUSSION.

a. The purpose of CAIPs is to provide owners, operators, surveyors, and marine inspectors with detailed information on the vessel's fracture history, corrosion control systems, and repair experience so that structural examinations can be focused upon existing or potential problem areas. The CAIP is intended to record the various repair methodologies employed, in order to ascertain which repairs or modifications have been effective over time. b. The aim of the CAIP program is to promote a proactive approach to structural repair which emphasizes identification and remediation of the underlying causes of the structural failure, rather than merely placing the symptoms. The scope and frequency of CAIP examination is predicated upon the gravity of the structural failures being experienced, and the vigor and success with which the underlying causes of the failures are being addressed. c. A CAIP is intended to be a dynamic program, to be modified and revised as circumstances dictate. NVIC 15-91 indicated that affected vessel owners or operators could apply to have certain areas removed from active monitoring, however, it did not provide specific procedural guidance for this process. d. The Coast Guard has been pleased with the level of cooperation, professionalism, and quality of information received from vessel owners, operators, and hull surveyors involved in the CAIPs program. As the industry and the Coast Guard have acquired operational experience with CAIPs, it is appropriate now to establish the procedures by which affected owners and operators can apply for modifications to their original CAIP requirements.

Critical Areas Inspection Plans (CAIPs) — PROCEDURES.

a. Owners or operators of U.S. vessels, required by the Commandant to develop and maintain CAIPs, who wish to modify the examination scope and/or interval originally imposed, shall apply to Commandant (G-MVI-1) via the Officer-in-Charge, Marine Inspection (OCMI) who has currently certificated the vessel. Owners or operators of foreign flag vessels who desire similar modifications shall apply to Commandant (G-MVI-1) via the OCMI in whose zone the last CAIP exam was conducted. Owners or operators of vessels required by an OCMI to develop and maintain CAIPs who desire changes from the examination scope and/or interval originally imposed shall apply directly to that OCMI. b. Vessel owners or operators may apply for CAIP modifications at any time. Applications must include the following information:

(1) Proposed modifications to scope and/or examination interval. The applicant must propose the modification desired. Modifications may include eliminating certain areas from periodic CAIP examination, downgrading certain areas from active repair areas to critical inspection areas, extending the interval between CAIP examinations, or a combination of these factors.

(2) Justification for the CAIP modification. The burden is on the applicant to justify why the desired CAIP modifications are appropriate. Modifications may be justified by a number of factors, which may be considered individually or in combination, depending upon the individual vessel's circumstances.

(a) A record of internal structural examinations which indicate that the area under consideration has not experienced a history of structural failure.

(b) Successful remedial efforts which addressed the cause of a structural failure, such as a detail modification, may justify a change in the CAIP. Generally, for purposes of amending a CAIP, a detail modification may be deemed successful if it has not fractured, nor redistributed a hard spot or stress riser to another location, within one year, or within the originally specified examination time interval, whichever is greater. Similarly, inserts and in situ repairs (gouge and reweld) may be deemed successful if no refracturing has occurred within one year or within the originally specified examination time interval, whichever is greater. Modifications which have significantly reduced the incidence and/or severity of fractures to the point where they no longer pose a threat to the structural or oil tight integrity of the vessel may also be considered "successful" for the purpose of supporting a CAIP modification, provided that similar unmodified details in the same tank have not experienced increased fracturing.

(c) Active repair areas experiencing recurrent Class 1 fractures will not be eligible for scope or interval relaxation. However, the presence or recurrence of certain Class 2 or "nuisance" type Class 3 fractures may not necessarily preclude increasing the CAIP examination interval in that active repair area. An appropriate fracture mechanics analysis should be submitted which demonstrates that Class 2 or Class 3 fractures will not propagate to critical length in the proposed time interval, using a safety factor of at least 2.5. Similarly, it may be possible to demonstrate that a change in the vessel's operational characteristics, such as route and speed changes, voyage planning programs to avoid encounters with adverse sea conditions, or alterations of loading or ballasting patterns, could reduce the stresses to which the vessel is subject, thereby increasing the time for a crack to propagate to critical length. An appropriate fracture mechanics analysis should take into account the identification of specific details, flaw size, fracture toughness of the plates studied, estimates of the equivalent root mean squared stress range to which a vessel is subject, and estimates of the resultant crack propagation life and a proposal for a reasonable examination interval. An example of a fracture mechanics methodology for oil tankers is provided as enclosure (1). Studies conducted for the purposes of increasing the CAIP inspection interval based upon fracture mechanics methodologies, and operational changes should be provided to the vessel's Classification Society for review and comment prior to submission to the Coast Guard.

(d) Examinations conducted by an International Association of Classification Societies (IACS) member classification society pursuant to the enhanced survey requirements for oil tankers required by the 1992 Amendments to Annex I of Regulations for the Prevention of Pollution by Oil 73/78, Regulation 13G, may be substituted for CAIP exams if shown to be substantially equivalent in scope, intent, and effect as the examinations conducted pursuant to CAIP requirements.

(e) Examinations conducted by an IACS member classification society pursuant to the enhanced survey requirements for bulk carriers established by IACS in response to the International Maritime Organization, Resolution 713(17) of 6 November 1991, may be substituted for CAIP exams if shown to be substantially equivalent in scope, intent, and effect as the examinations conducted pursuant to CAIP requirements.

(f) The additional factors presented in support of the proposed modification will dictate the degree of enhanced survey substitution permitted. Substitution could be limited to a one time grant to extend the CAIP exam to coincide with an enhanced survey. Alternatively, if conditions warrant, the scope and frequency of the enhanced survey might be accepted in place of the CAIP requirements entirely.

(3) Baseline examination data. The baseline examination data is the vessel's structural condition as it existed following its first CAIP exam. Information concerning the type, amount, and location of fractures found, and the repairs effected, should be indicated. In most cases, this information should already be documented as part of the historical information recorded in the vessel's CAIP portfolio. If so, the applicant need only reference the pertinent entry in the CAIP portfolio. It is the applicant's responsibility to ensure that the reviewing authorities are provided with copies of all relevant information.

(4) Latest examination data. The latest examination data is the vessel's structural condition as found at the most recent CAIP examination, internal structural examination (ISE), or enhanced survey. The latest examination includes all critical inspection areas and active repair areas as defined in NVIC 15-91. The latest examination data must identify the type, amount, and location of repairs, such as detail modifications, inserts, gouge and reweld, etc., which have been effected since the baseline exam, and the success of the repair methodology. The latest examination data must indicate if any new fractures or structural discrepancies have been discovered, and the repair methodology employed, as applicable.

(5) Endorsement by classification society. Owners or operators of classed vessels must include a favorable endorsement of their proposed CAIP modification from their classification society.

Critical Areas Inspection Plans (CAIPs) — IMPLEMENTATION.

a.

Owners and operators who wish to modify their vessel's CAIP requirements shall follow the procedures specified in paragraph 5 of this Circular.

The latest examination must be conducted and witnessed by the relevant OCMI (the OCMIs identified in paragraph 5.a of this Circular).

Owners and operators contemplating CAIP modifications must contact their relevant OCMIs and provide them with adequate notice of the time and location where the latest examination is to be conducted. b.

OCMIs shall attend CAIP examinations to the extent they deem necessary to verify the applicant's findings, and to permit them to make an informed recommendation concerning the propriety of accepting the applicant's modification proposal. c.

OCMIs shall review all CAIP modification requests to ensure that the applicant has provided the necessary information required by paragraph 5.b of this Circular.

OCMIs may approve modifications to all CAIPs for which they were the implementing authority.

OCMIs shall forward modification requests for all other CAIPs, with their recommendations, to Commandant (G-MVI) via District Commander (m). d.

Commandant (G-MVI-1) will review applicants' requests and make the decision whether or not to accept the proposed modifications based upon the information provided by the applicant, the endorsement of the cognizant classification society or authority which has issued the vessel's Safety Construction Certificate (if applicable), the recommendation of the relevant OCMI and District Commander (m), and a review of the vessel's CAIP record.

Commandant (G-MVI-1) will provide applicants with written decisions which specify the new terms of the CAIP, as applicable. e.

Vessel owners or operators shall amend and maintain their vessel's CAIPs to reflect any changes accepted by cognizant Coast Guard authorities. f.

OCMIs are urged to give this Circular wide dissemination.

OCMIs are encouraged to work with affected vessel owners and operators to ensure that the ultimate aim of the CAIP program, effective tracking and management of the vessel's structural condition, continues to be realized.

J.

C.

CARD Rear Admiral, U.S.

Coast Guard Chief, Office of Marine Safety, Security and Environmental Protection Encl: (1) Fracture Mechanics Methodology For Fracture Control In Oil Tankers Non-Standard Distribution: C:e New Orleans (90); Hampton Roads (50); Baltimore (45); San Francisco, Puget Sound (40); Philadelphia, Port Arthur, Honolulu (35); Miami, Houston, Mobile, Long Beach, Morgan City, Portland OR (25); Jacksonville (20); Boston, Portland ME, Charleston, Galveston, Anchorage (15); Cleveland (12); Louisville, Memphis, Paducah, Pittsburgh, St.

Louis, Savannah, San Juan, Chicago, Detroit, Duluth, Milwaukee, Buffalo, San Diego, Juneau, Valdez (10); Providence, Huntington, Wilmington, Corpus Christi, Toledo, Guam, Sault Ste.

Marie (5).

C:m New York (70); Sturgeon Bay (4).

D:d Except Baltimore and Moriches.

D:1 CG Liaison Officer MILSEAIFTCOMD (Code N-7CG), CG Liaison Officer RSPA (DHM-22), CG Liaison Officer MARAD (MAR-742), CG Liaison Officer JUSMAGPHIL, CG Liaison Officer World Maritime University, CG Liaison Officer ABS, Maritime Liaison Office Commander U.S.

Naval Forces Central Command (1).

NOAA Fleet Inspection Officer (1).

U.S.

Merchant Marine Academy (1). ---