rules for classification underwater technology

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DNV GL AS

RULES FOR CLASSIFICATION

Underwater technologyEdition January 2016

Part 7 Systems in service

Chapter 1 Survey requirements

FOREWORD

DNV GL rules for classification contain procedural and technical requirements related to obtainingand retaining a class certificate. The rules represent all requirements adopted by the Society asbasis for classification.

© DNV GL AS January 2016

Any comments may be sent by e-mail to [email protected]

If any person suffers loss or damage which is proved to have been caused by any negligent act or omission of DNV GL, then DNV GL shallpay compensation to such person for his proved direct loss or damage. However, the compensation shall not exceed an amount equal to tentimes the fee charged for the service in question, provided that the maximum compensation shall never exceed USD 2 million.

In this provision "DNV GL" shall mean DNV GL AS, its direct and indirect owners as well as all its affiliates, subsidiaries, directors, officers,employees, agents and any other acting on behalf of DNV GL.

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Rules for classification: Underwater technology — DNVGL-RU-UWT-Pt7Ch1. Edition January 2016 Survey requirements

DNV GL AS

CURRENT – CHANGES

This document supersedes the December 2015 edition.

Main changes January 2016, entering into force as from date ofpublication

• General— The entry into force date has been changed from July 2016 to January 2016.

Editorial correctionsIn addition to the above stated changes, editorial corrections may have been made.

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CONTENTS

Current – changes.................................................................................................. 3

Section 1 General....................................................................................................61 Introduction.........................................................................................6

Section 2 Survey requirements for manned hyperbaric systems.............................81 General................................................................................................ 82 Annual survey......................................................................................83 Intermediate survey.......................................................................... 114 Renewal survey................................................................................. 115 Survey of hyperbaric systems out of commission.............................. 13

Section 3 Saturation and surface oriented diving systems....................................151 General.............................................................................................. 15

Section 4 diving simulators...................................................................................161 General.............................................................................................. 16

Section 5 Self-contained diver pressure chambers............................................... 171 General.............................................................................................. 17

Section 6 manned submersibles............................................................................181 General.............................................................................................. 182 Performance of surveys.....................................................................183 Damage Survey..................................................................................204 Extraordinary Survey......................................................................... 205 Survey of submersibles 'out of commission'......................................21

Section 7 Remotely operated vehicles.................................................................. 221 General.............................................................................................. 222 Class surveys.....................................................................................22

Section 8 Autonomous underwater vehicles......................................................... 251 General.............................................................................................. 25

Section 9 Underwater working machines..............................................................261 General.............................................................................................. 26

Section 10 Surveys for supporting systems on board the support vessel.............. 27

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1 Surveys for supporting systems aboard ships................................... 272 Surveys for stowage on board and deck transport.............................273 Surveys for launch and recovery systems..........................................27

Section 11 Spare parts..........................................................................................281 General.............................................................................................. 282 Spare Parts for manned submersibles............................................... 283 Spare Parts for other underwater systems........................................ 28

Changes – historic................................................................................................29

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SECTION 1 GENERAL

1 IntroductionClassed underwater systems in operation shall be surveyed periodically and shall fulfil special requirementswhich are laid down in this chapter.

1.1 ApplicationThis chapter applies to the following underwater systems in service regarding requirements for surveys formaintenance of class:

— diving simulators— diver pressure chambers— manned submersibles— remotely operated vehicles— autonomous underwater vehicles— underwater working machines and systems.

The general requirements in this section apply to all underwater systems whereas the special requirementsare considered in the individual sections. The general items of SHIP Pt.7 Ch.1 do apply also for this chapter.

1.2 ReferencesReference Title

ASME PVHO-2 “In-Service Guidelines for PVHO acrylic windows”

EN12021 Compressed air for breathing apparatus

1.3 Kinds of surveys

1.3.1 DNV GL classed UWT Systems shall be subjected to the following surveys, if their class shall bemaintained:

— Annual survey.— Intermediate survey

The intermediate survey falls due nominally 2.5 years after commissioning and each class renewal and maybe carried out on the occasion of the second or third annual survey.Any deviations of the survey schedule regarding operation time shall be agreed with the Society.

— Renewal survey after five years.— Damage survey, where the underwater system or parts thereof have suffered damage liable to affect the

serviceability of the underwater system.

1.3.2 The Society reserves the right to demand for extraordinary surveys in justified cases. Such surveysmay be credited against the prescribed regular surveys.

1.4 Explanatory notes on surveys

1.4.1 The locally responsible surveyor shall be given timely notice when regular surveys become due orwhen it is intended to carry out repairs or alterations, so that the work can be supervised.

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1.4.2 The records of each survey, as well as special requirements upon which the maintenance of classhas been made conditional, will be entered in the classification certificate. In addition to the character ofclassification and the month and year of classification, the register book shall also state the month and yearof the last annual survey or the last renewal survey.The original class certificate with evidence marking of the last surveys shall be available on the place ofoperation.

1.4.3 Apparatus and components shall be arranged accessible for surveys. If it is either not possible orexcessively costly to prepare these for survey on board, surveys may also, on application, be performed inthe manufacturer's works or another authorized workshop.

1.4.4 Where defects are repaired provisionally only, or where the surveyor does not consider immediaterepairs or replacements necessary, the class of the submersible may be confirmed for a certain limited periodby making an entry in the certificate of classification.The withdrawal of such restrictions will be entered in the certificate of classification as well.

1.4.5 Where parts are damaged or worn to such an extent that they no longer comply with the requirementsof the Society, they shall be repaired or replaced.Any damage shall be reported.Any major repairs shall be agreed with the Society.

1.4.6 If an underwater system shall be surveyed in a port or place where, or near which, there is no agentof or Society's surveyor, the locally responsible consul, a competent office or authority, or the averagecommissioner of the insurance company concerned shall be requested to cause the underwater system tobe surveyed by an expert. The commission of the expert shall be confirmed by the consul, the office orauthority, or the average commissioner. The consulted expert shall be requested to forward to the Societyforthwith a report on the condition of the underwater system and on the repairs as well as on the decisionarrived at. A copy of the report shall be retained close to the underwater system. The decision of theexpert is subject to the approval of the Society, who will decide on whether the underwater system shall besurveyed again.

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SECTION 2 SURVEY REQUIREMENTS FOR MANNED HYPERBARICSYSTEMS

1 General

1.1 These requirements apply to transferable hyperbaric systems, where the regular periodical surveys arecarried out when such systems are in service.When transferable hyperbaric systems are out of commission, annual surveys as described in [2] shall becarried out.

1.2 Survey Planning DocumentA Survey Planning Document shall be part of the documentation for the lifetime of the hyperbaric system ifrequested by the Society.

1.2.1 For transferable hyperbaric systems, the Survey Planning Document shall specify scope for surveyswhen the system is installed and for surveys when the system is in storage (laid-up).

1.2.2 The Survey Planning Document shall be written in English (or translated into English), and approved bythe Society prior to the survey taking place. Checklists shall be included, as attachments.It shall have the following information printed on the front page:

— Diving System Survey Planning Document (title)— name of support vessel or place of installation given in the classification register— the Society’s identity number given in the classification register— IMO number (for statutory surveys), if applicable— name of operating company— revision number and date.

Guidance note:A Survey Planning Document gives owners and surveyors a chance to tailor the instructions to fit each individual system or componentand thereby avoid misunderstandings often encountered with respect to the application of generic requirements. This may alsostreamline the surveys in consideration of the operational situations in each case.

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Checklists shall be made available for the surveyor to fill out and endorse at each survey. The checklists shallinclude the following information at the top of each page:

— name of support vessel or place of installation given in the classification register— the Society’s identity number given in the classification register— IMO number (for statutory surveys), if applicable— page number and total page number— name of operating company— scope of survey (annual, intermediate, renewal or otherwise)— in columns: Survey item, condition, action, comment.

2 Annual surveyThe survey shall include the following items.Further specification of test requirements especially the installation on board ships are given in the relevantsections of SHIP Pt.7 Ch.1.

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2.1 Check of readings and calibration of essential instrumentation (depth gauges, gas analysers, etc.)

2.2 Switching from main to emergency electrical power supply

2.3 Examination of the documents relating to the hyperbaric system and scrutiny of the operational records.

2.4 Inspection for visible damages, cracks, deformation, corrosion and fouling etc. of the entire chamber systemincluding all fixtures, penetrations, window frames, doors and covers, seals, locking systems, etc.

2.5 Check of measures for corrosion protection (e.g. anodes).

2.6 External inspection of all other pressure vessels and apparatus under external and internal overpressure,valves, fittings and safety equipment.

2.7 External inspection of the entire machinery plant including electrical installations and gas supply system forthe chamber system and all redundant systems.

2.8 Check that insulation measurements have been performed on the electrical equipment.

2.9 Review and functional test of safety systems including safety valves.

2.10 Functional test of all alarm systems.

2.11 All emergency systems are to undergo a functional test (e.g. the autonomous gas supply of the divingchamber)

2.12 Functional test on mating and de-mating of the hyperbaric rescue system if applicable.

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2.13 Tightness tests of the life support systems.

2.14 Simulation of the function of the fire detection-, alarm- and extinguishing systems without discharge ofextinguishing agent.

2.15 All hose lines for the gas supply and gas filling as well as the hoses of the diver’s heating and the umbilicalsshall be checked for visible damages and tightness.

2.16 Acrylic windows shall be subjected to a visual check for cracks, scratches, changes of structure (crazing). Asfar as possible at installed condition, the contact area, retaining rings and window sealing shall be checked.

2.17 Umbilical and lifting cable shall be checked for visible damages, cracks, deformations and corrosion.

2.18 Function of the main and emergency communication systems shall be checked.

2.19 If compressors for breathing air are used the quality of the compressed air shall be proven, e.g. according toEN 12021.

2.20 The mating arrangement will be checked for visible damages, cracks, deformations and corrosion attacksand, as far as possible, subjected to a functional test.

2.21 The launch and recovery system including all fixed and variable load transmitting devices shall be checked forvisible damages, cracks, deformations and corrosion.

2.22 The systems for safe stowage and safe deck transport aboard the diver support ship or the place ofinstallation shall be reviewed.

2.23 The supply systems which are necessary for the safe operation of the hyperbaric system and their controlaboard the diver support ship or the place of installation shall be checked.

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2.24 The functional efficiency of the total system shall be checked by means of a trial dive.

3 Intermediate surveyAn intermediate survey shall cover the annual survey according to [2] extended by the following scope:

3.1 Performance of a tightness test on the entire hyperbaric system at maximum permissible working pressureusing air.Testing shall include external and internal barriers i.e. doors, medical/equipment locks etc.

3.2 Verification of the set pressures and reset pressures of compression chamber safety valves (functional test)and of safety and warning systems.

3.3 Functional tests on mechanical and electrical systems.

3.4 Functional test of life support systems and purity check on all breathing gas compressors.

3.5 Functional test of the fire detection-, alarm- and extinguishing systems

4 Renewal surveyIn addition to the surveys defined in [2] and [3] the following tests and examinations shall be carried out fora renewal survey every five years:

4.1 Bell buoyancy materials, heat protection, penetrators, windows, if necessary and attached members shall bedismounted for inspection for possible corrosion and deterioration.

4.2 Pressure tests and inspections shall be carried out according to an approved procedure e.g as given in theSurvey Planning Document.Pressure test marking shall be stamped on the pressure vessels according to the design code or, if notpossible, engraved on an attached tag and given in the accompanying certificate.Applicable codes, standards and regional requirements shall be specified in the procedure.Pressure testing shall be carried out according to the design code of the pressure vessel and to internationalstandards for such testing.

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Guidance note:International testing standards include EN 1968 Transportable gas cylinders - Periodic inspection and testing of seamless steel gascylinders.The applicable working pressure and corresponding filling ratios should meet the requirements in BS5355 Filling ratios and developedpressures for liquefiable and permanent gases or equivalent standard.Regional requirements may also apply, such as the HSE Approved Specification Number CP1-3T Specification for Large seamless steel(897 to 1069 N/mm2) Transportable Gas Containers or Code of Federal Regulations Title 49 Ch.I Part 178 Subpart C Sec.178.45Specification 3T seamless steel cylinder. (CITE: 49CFR178.45 US DOT).

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4.3 Proof test or volumetric expansion test shall be carried out according to that which is required by the designcode or regional requirements.

4.4 Pneumatic testing shall not be carried out at pressures above 1.1 x maximum allowable working pressure.

4.5 At 1st renewal survey the interval for hydraulic pressure testing of gas containers may be extended to 10years if the following principles are applied:

— External and internal survey.— If internal survey is not possible or if corrosion or other items of concern are found, hydraulic test shall be

carried out to the test pressure determined by the design code.

At all subsequent renewal surveys:

— External and internal survey.— Hydraulic test to the test pressure determined by the design code.

4.6 At 1st renewal survey the interval for hydraulic pressure testing of chambers (and bell) may be extended to10 years if the following principles are applied:

— External and internal survey.— If internal survey is not entirely possible or if corrosion or other items of concern are found, hydraulic test

shall be carried out to the test pressure determined by the design code.— Alternatively, pneumatic test to the working pressure may be carried out and the pressure vessel down

graded, see [4.4].

At all subsequent renewal surveys:

— External and internal survey.— Hydraulic test to the test pressure determined by the design code.— Alternatively, pneumatic test to the working pressure may be carried out and the pressure vessel down

graded, see [4.4].

4.7 Windows with an age of 10 years or more shall be changed unless a special survey warrants an extension.

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The special survey shall be carried out to a procedure approved by the Society in accordance with e.g. ASMEPVHO-2-2012 In-Service Guidelines for PVHO acrylic windows.

4.8 Visual check of all fastenings, bearing and coupling elements of all machinery and devices.

4.9 Pressure chambers and locks shall be subjected to functional tests and a tightness test with maximumallowable working pressure and the actual operating medium.

4.10 Check of the structural areas which are not or not easily accessible with the aid of non-destructive testprocedures.The non-destructive testing (NDT) procedure shall be agreed with the Society.

4.11 Dimensional checks and non-destructive wall thickness tests shall be performed on the pressure chambersand especially the diving chamber. Where necessary, buoyancy aids, cladding and layers of thermal insulationshall be removed for this purpose.

4.12 Internal inspection of vessels and apparatus under pressure. If these cannot be satisfactorily inspectedinternally or their satisfactory condition cannot be fully verified by internal inspection, another non-destructive test method shall be used and/or a hydraulic pressure test shall be performed. Where necessary,buoyancy aids, claddings and layers of thermal insulation shall be removed for this purpose.

4.13 Check that accessories, especially hose assemblies and compensators are changed according to themaintenance plan.

4.14 Where surveys are performed on a hyperbaric system or parts thereof during the period of class the scope ofwhich corresponds to a renewal survey, then the regular renewal survey for the parts concerned may at theoperator’s request be deferred accordingly.

5 Survey of hyperbaric systems out of commission

5.1 Hyperbaric systems which have been out of commission, i.e. laid up, for a period normally of at least 12months, shall be surveyed and tested before re-entering service. The extent of the surveys and tests will beconsidered in each case depending upon:

— the time the hyperbaric system has been out of commission— the maintenance and preservative measures taken during lay-up

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— the extent of surveys carried out during this time.

As a minimum, a sea trial for function testing of the hyperbaric system shall be carried out.

5.2 During lay-up, hyperbaric system installed on board shall be subjected to a lay-up survey on an annual basis.The extent of the lay-up survey is reduced compared to the regular annual survey, but shall cover systemintegrity, planned maintenance system, fire protection and equipment in use.

5.3 If the lay-up period is more than 12 months, other periodical surveys may be postponed, depending on themaintenance and preservative measures taken during lay-up.

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SECTION 3 SATURATION AND SURFACE ORIENTED DIVINGSYSTEMS

1 GeneralThe requirements in this section apply to diving systems with class notation:SAT and SURFACE.For performance of periodical and extraordinary surveys of saturation and surface oriented diving systemsplease refer to the survey requirements in DNVGL DSS-105. All applicable requirements shall be observedand fulfilled.

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SECTION 4 DIVING SIMULATORS

1 GeneralFor performance of periodical and extraordinary surveys of diving simulators, please refer to the surveyrequirements in Sec.2. All applicable requirements of Sec.2 shall be observed and fulfilled.

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SECTION 5 SELF-CONTAINED DIVER PRESSURE CHAMBERS

1 GeneralFor performance of periodical and extraordinary surveys of hyperbaric reception facilities, please refer to thesurvey requirements in Sec.2. All applicable requirements of Sec.2 shall be observed and fulfilled.

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SECTION 6 MANNED SUBMERSIBLES

1 General

1.1 The requirements in this section apply to manned submersibles with class notation:SUBMERSIBLE.

1.2 When manned submersibles are out of commission, annual surveys as described in below shall be carriedout.

2 Performance of surveysThe surveys shall be performed according to the following criteria. If the operational systems of asubmersible should be different from the standard case, the scope of the surveys may be adjustedaccordingly in coordination with the Society.

2.1 Annual SurveyThe annual survey of the submersible shall include at least the following tests and checks:

2.1.1 Examination of the documents relating to the submersible and scrutiny of the operational records.

2.1.2 The pressure hull outside and inside and external structure including all fixtures, penetrations,viewports, doors and covers, seals, locking systems, etc. shall be inspected for visible damage, cracks,deformation, corrosion and fouling, etc.

2.1.3 Check of the measures for corrosion protection (e.g. anodes).

2.1.4 All other pressure vessels and apparatus under external or internal pressure, pipes, valves, armatures,fittings and safety equipment shall be subjected to external inspection.

2.1.5 The entire machinery installation and the electrical equipment including all redundancy systems shallbe subjected to external inspection.

2.1.6 Check that insulation measurements have been performed on the electrical equipment.

2.1.7 Review of safety systems including response pressure of the safety valves and the set points of thesafety devices.

2.1.8 Function test of all alarm systems.

2.1.9 Switching from the main to the emergency electricity supply shall be tested.

2.1.10 The accuracy of all essential instrument readings shall be checked (e.g. depth gauge, gas analyzer,etc.).

2.1.11 All emergency and safety systems (e.g. jettisoning mechanism, marking buoy, rescue devices) are toundergo a functional test – as far as appropriate.

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2.1.12 Functional test of all life support systems.

2.1.13 Tightness test of the life support systems and of the ballast system at maximum allowable workingpressure.

2.1.14 Review of the function of the fire surveillance and extinguishing systems.

2.1.15 Hose lines shall be checked for visible damages.

2.1.16 Acryl windows shall be subjected to a visual check for cracks, scratches, changes of structure(crazing) and discolouration . As far as possible at installed condition, the contact area and the windowsealing shall be checked.

2.1.17 The umbilical and lifting cable (if applicable) shall be checked for visible damages, cracks,deformations and corrosion.

2.1.18 The function of data transfer and communication systems shall be checked.

2.1.19 If compressors for breathing air are used the quality of the compressed air shall be proven, e.g.according to EN 12021.

2.1.20 Compression chambers/diver lockouts of the submersible shall be subjected to functional tests and atightness test at maximum allowable diving pressure with the relevant operational media.

2.1.21 The mating arrangement of the submersible, if applicable, will be checked for visible damages,cracks, deformations and corrosion and, as far as possible, subjected to a functional test.

2.1.22 The functional efficiency of the total system shall be checked by means of a trial dive.

2.2 Intermediate SurveyAn intermediate survey is an annual survey according to [2.1] extended by the following scope.

2.2.1 Performance of a tightness test on pressure hull penetrations and closing appliances by application of avacuum of at least 0.2 bar below atmospheric pressure.

2.2.2 Tightness test on lockable diving tanks which can be shut off using air at a test pressure ofapproximately 0.2 bar preferable at the completely dived submersible respectively tightness test of theventilation valves for open diving tanks.

2.2.3 Tightness test on pressure vessels under external pressure by underpressure test with at least 0.2 barbelow atmospheric pressure or other suitable test procedure, as far as required.

2.2.4 Tightness test of the compensating system.

2.2.5 Tightness test of hose lines.

2.2.6 External visual check and functional test, if applicable, of the extension elements/working devicesbelonging to the submersible.

2.3 Renewal SurveyIn addition to the surveys defined in [2.2] the following tests and examinations shall be carried out forrenewal surveys:

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2.3.1 Visual check of the fastenings, bearing and coupling elements of all machinery and devices.

2.3.2 Inspection of the shell cladding and buoyancy aids (pressure resistant foam) from all sides. Ifnecessary the cladding shall be removed.

2.3.3 Dimensional checks and non-destructive wall thickness tests shall be performed on the pressure hulland the diver's lockout. Where necessary, buoyancy aids, cladding and layers of thermal insulation shall beremoved for this purpose.

2.3.4 Check of the structural areas which are not easily accessible with the aid of non-destructive testprocedures.

2.3.5 An emergency ballast release followed by a buoyancy test shall be performed.

2.3.6 Internal visual check of vessels and apparatus under pressure. If these cannot be satisfactorilyinspected internally or their satisfactory condition cannot be fully verified by internal inspection, another non-destructive test method shall be used and/or a hydraulic pressure test shall be additionally performed. Thiscan be a pressure test with 1.5 x maximum allowable working pressure. Where necessary, buoyancy aids,cladding and layers of thermal insulation shall be removed for this purpose.

2.3.7 The examinations according to [2.1.16] shall be performed for dismantled acrylic windows where partsof the window are covered, not easy visible or any doubts of the window condition are raised.

2.3.8 Check that accessories, especially hose lines and compensators are changed according to themaintenance plan.

2.3.9 Where surveys are performed on a submersible or parts thereof during the period of cass, the scope ofwhich corresponds to a renewal survey, then the regular renewal survey for the parts concerned may at theoperator's request be deferred accordingly.

3 Damage SurveyEach damage shall be reported to the Society.

3.1 If the submersible has suffered damage affecting its class or if such damage may be assumed, a damagesurvey shall be carried out.

3.2 Following damage, the submersible shall be presented for survey in such a way that a satisfactory inspectioncan be carried out. The scope of the damage survey will be determined by the Society in each individualcase.

4 Extraordinary Survey

4.1 When any modification is made in respect of design, mode of operation or equipment, and after major repairsto the submersible, an extraordinary survey shall be carried out.

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4.2 Where modifications are made to the submersible which affect its buoyancy or stability, appropriate heelingand trim tests shall be performed in the presence of the the Society's surveyor.

5 Survey of submersibles 'out of commission'

5.1 Submersibles which have been out of commission, i.e. laid up, for a period normally of at least 12 months,shall be surveyed and tested before re-entering service. The extent of the surveys and tests will beconsidered in each case depending upon:

— the time the submersible has been out of commission— the maintenance and preservative measures taken during lay-up— the extent of surveys carried out during this time.

As a minimum, a sea trial for function testing of the submersible shall be carried out.

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SECTION 7 REMOTELY OPERATED VEHICLES

1 General

1.1 The requirements in this section apply to remotely operated vehicles (ROV) with class notation: ROV

1.2 Surveys to be performed in the course of the constructional tests and acceptance tests on the ROVs areperformed by the Society in accordance with these rules in agreement with the manufacturer or operator. Forthis scope see Pt.5 Ch.7 Sec.2 [6].

1.3 Surveys required under official regulations, international conventions or other arrangements are performedby the Society on application or commission as required by the relevant provisions.

1.4 If the ROV has suffered substantial damage which impairs or nullifies the validity of the certificate, theSociety will on application carry out damage and repair surveys and confirm the certificate after thenecessary repair measures have been performed.

1.5 Extraordinary surveys have to be carried out if modifications are made in respect of design, mode ofoperation or equipment.

1.6 If it is an excessive effort to prepare units and components for survey on board, the surveys may also, onapplication, be performed at the manufacturer's works or another authorized workshop.

2 Class surveysThe surveys shall be performed according to the following criteria. If the operational systems of asubmersible should be different from the standard case, the scope of the surveys may be adjustedaccordingly in agreement with the Society.

2.1 Annual surveyThe annual survey of the ROV includes at least the following tests and checks:

2.1.1 Examination of the documents relating to the submersible and scrutiny of the operational records.

2.1.2 The exostructure including the load bearing structure, all fixtures, doors and covers, lifting points,claddings, fixed buoyancy aids, etc. shall be inspected for visible damage, cracks, deformation, corrosionattacks and fouling, etc.

2.1.3 Check of the measures for corrosion protection (e.g. anodes).

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2.1.4 All vessels and apparatus under external or internal overpressure, penetrations, viewports, valves,fittings and relevant safety equipment shall be subjected to external inspection.

2.1.5 The entire machinery installation including electrical equipment and eventual redundancy systems shallbe subjected to external inspection.

2.1.6 Check that insulation measurements have been performed on the electrical equipment.

2.1.7 Review of safety systems and of the set points of the safety devices.

2.1.8 Function test of all alarm systems.

2.1.9 Switching from the main to the emergency electricity supply of the submersible, if existing, shall betested.

2.1.10 The accuracy of all essential instrument readings shall be checked (e.g. depth gauge, etc.).

2.1.11 All emergency systems (e.g. release mechanism, emergency signals) are to undergo a functional testas far as applicable.

2.1.12 Check of the ballast system.

2.1.13 Hose assemblies shall be checked for visible damages.

2.1.14 The umbilical and lifting cable if applicable shall be checked for visible damages, cracks, deformationsand corrosion.

2.1.15 The function of the equipment for data transfer shall be checked.

2.1.16 Fixed installed and variable buoyancy elements shall be checked.

2.1.17 The functional efficiency of the total system shall be checked by means of a trial dive.

2.2 Intermediate surveyThe intermediate survey falls due nominally 2.5 years after commissioning and each class renewal and maybe carried out on the occasion of the second or third annual survey.An intermediate survey is an annual survey according to [2.1] extended by the following scope:

2.2.1 Performance of a tightness test on vessels under external pressure by application of a vacuum of atleast 0.2 bar below atmospheric pressure or other suitable test procedures, as far as applicable.

2.2.2 Tightness test of ballast water system, if existing.

2.2.3 Tightness test of hose assemblies.

2.2.4 External visual check and eventual functional test, if applicable, of the extension elements/workingdevices belonging to the submersible.

2.3 Renewal surveyEvery five years a renewal survey will be carried out. In addition to the surveys defined in [2.2] the followingtests and examinations shall be carried out for renewal surveys:

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2.3.1 Check of the shell cladding and buoyancy aids (pressure resistant foam) from all sides incl. variableblocks e.g. for umbilicals. If necessary the cladding shall be removed.

2.3.2 Check of the areas of the load bearing structure which are not easily accessible with the aid of non-destructive test procedures.The test procedures shall be agreed with the Society.

2.3.3 For vessels and apparatus under pressure, which cannot be satisfactorily inspected internally or theirsatisfactory condition cannot be fully verified by internal inspection, another non-destructive test methodshall be used or a hydraulic pressure test shall be performed additionally. As far as necessary buoyancymaterials, cladding or heat insulation layers shall be removed.

2.3.4 Acrylic windows and glass panes (e.g. of spotlights) shall be dismantled, if necessary, and shall bechecked for cracks. The window seatings shall be checked for corrosion and damages.

2.3.5 Check of systems for emergency surfacing and the resulting floating condition at the water surface.

2.3.6 Check that accessories, especially hose assemblies and compensators have been changed according tothe maintenance plan.

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DNV GL AS

SECTION 8 AUTONOMOUS UNDERWATER VEHICLES

1 General

1.1 The requirements in this section apply to autonomous underwater vehicles (AUV) with class notation: AUV

1.2 For performance of periodical and extraordinary surveys of AUVs please refer to the survey requirements inSec.7. All applicable requirements of Sec.7 shall be observed and fulfilled.

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DNV GL AS

SECTION 9 UNDERWATER WORKING MACHINES

1 General

1.1 The requirements in this section apply to underwater working machines with class notation: UWM

1.2 For performance of periodical and extraordinary surveys of underwater working machines, please refer to thesurvey requirements in Sec.7. All applicable requirements of Sec.7 shall be observed and fulfilled.The survey includes check of documents for the working machine respectively the working device andinspection of the operational records.The complete system shall be checked for visible damages, cracks, deformations and corrosion attacks.The complete system shall be subjected to a functional test.Further tests specific to the machine shall be agreed with the Society case by case.

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DNV GL AS

SECTION 10 SURVEYS FOR SUPPORTING SYSTEMS ON BOARD THESUPPORT VESSEL

1 Surveys for supporting systems aboard shipsWithin repeated surveys the complete system shall be checked for visual damages, cracks, deformations andcorrosion and shall be subjected to a functional test for normal and emergency operation.

2 Surveys for stowage on board and deck transportFor maintaining the certificate the systems shall be subjected to an annual survey.For this the complete system including all lashing and transport devices shall be checked for cracks,deformations and corrosion and shall be subjected to a functional test.

3 Surveys for launch and recovery systemsFor maintaining the certificate the launching and recovery system shall be subjected to an annual survey.For this the complete system including all lifting tackles shall be checked for visible damages, cracks,deformations and corrosion and shall be subjected to a functional test including a brake test (power failure).Every 5 years a dynamic test with 1.25 times SWL including a brake test (power failure) shall be performed.The applied loads may deviate from the loads mentioned above according to the applied design standard andshall be agreed with the Society.

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DNV GL AS

SECTION 11 SPARE PARTS

1 General

1.1 Spare Parts for manned hyperbaric systemsManned hyperbaric systems shall be provided with spare parts to enable continuous diving operations.

2 Spare Parts for manned submersibles

2.1 Independent manned submersiblesIndependent submersibles shall be provided with spare parts.

2.1.1 In order to restore machinery operation and manoeuvring capability of the submersible in the event ofa damage at sea, spare parts for the main propulsion plant and the essential equipment shall be carried onboard together with the necessary tools.

2.1.2 For batteries arranged within the pressure hull a sufficient set of cables with adequate cross section tobridge parts of the batteries or single cells shall be on board.

2.1.3 The scope of spare parts shall be documented, see Pt.5 Ch.6, and a relevant listing shall be on board.

2.2 Autonomous and Non-autonomous manned submersiblesIn case of submersibles which can only operate in conjunction with or are supplied by a support vessel spareparts shall be on board of the support vessel.

2.2.1 In order to restore the operation of the submersible in the event of damage at sea, spare parts for themain propulsion plant and the essential equipment together with the necessary tools shall be kept on boardof the support vessel.

2.2.2 The scope of spare parts shall be documented and a relevant listing shall be kept on board of thesupport vessel.

3 Spare Parts for other underwater systems

3.1 This section refers to:

— ROVs— AUVs— Underwater working machines

3.2 The requirements for spare parts for the above mentioned systems are stated in [2.2].

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DNV GL AS

CHANGES – HISTORIC

December 2015 edition

GeneralThis is a new document.The rules enter into force 1 July 2016.

DNV GLDriven by our purpose of safeguarding life, property and the environment, DNV GL enablesorganizations to advance the safety and sustainability of their business. We provide classification andtechnical assurance along with software and independent expert advisory services to the maritime,oil and gas, and energy industries. We also provide certification services to customers across a widerange of industries. Operating in more than 100 countries, our 16 000 professionals are dedicated tohelping our customers make the world safer, smarter and greener.

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rules for classification underwater technology

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