Section 1 General

1.1.1 These Provisional Rules apply to ships on which plant is installed for the purpose of stimulation of wells for the production of oil or gas from Offshore Installations.

1.1.2 The requirements of LR's published Rules and Regulations for hull, machinery and the well stimulation plant are to be complied with as applicable, namely:

1.1.3 Requirements additional to these Rules may be imposed by the National Authority with whom the ship is registered and/or by the Administration within whose territorial jurisdiction the ship is intended to operate.

1.1.4 The requirements of these Provisional Rules are based on the assumptions that hazardous liquids or substances will be carried and used in the process, e.g. flammable liquids having a flash point not exceeding 60°C (closed cup test) and corrosive acids. Where it is intended that only non-hazardous liquids or substances will be carried and used then the requirements will be modified, where necessary, to take account of the lesser hazards.

1.2.1 A ship provided with well stimulation plant in accordance with these requirements will be eligible for the class notation Offshore Well Stimulation Ship.

1.2.2 Additional class and/or special feature notations may be assigned where appropriate in accordance with Pt 1, Ch 2 Classification Regulations of LR's Rules and Regulations for the Classification of Ships (hereinafter referred to as Rules for Ships).

1.3.1 The arrangements and plant referred to in this Chapter are to be examined and tested on completion of the installation and subsequently annually.

1.4.1 The following plans and information are to be submitted:

• A general arrangement plan showing arrangements and disposition of the well stimulation plant.
• A plan showing structural arrangement in way of the plant fitted.
• Arrangements and details of storage tanks.
• Tank sounding and venting systems.
• Pumping and piping arrangements.
• Instrumentation and control for handling and storage of fluids/substances used for well stimulation purposes, including palletized deck loaded well stimulation packages, where applicable.
• A plan showing Hazardous Area designations.
• Emergency shutdown arrangements.
• Ventilating arrangements and access to control rooms or other enclosed areas.
• Fire protection, detection and extinction arrangements.
• Electrical equipment installations.
• Control engineering systems.
• Details of the flammability, toxicity or reactivity of any substance/fluid utilized or stored onboard.

1.5.1 The integrity of the weather deck is to be maintained. Where items of equipment such as cable leads penetrate the weather deck, adequate arrangements are to be provided to prevent the ingress of water to spaces below the freeboard deck. Otherwise such items are to be fully enclosed in deck houses, or equivalent, complying with the Rules. Structural strength in way of such arrangements is to be equivalent to Rule requirements for this purpose.

1.5.2 All accommodation and other compartments not directly essential to the operation of the well stimulation plant are to be arranged well clear of the plant, storage and operational areas. The control consoles are to be so sited that the stimulation activities can be kept under constant observation throughout the operation.

1.5.3 Tanks for liquefied gases and acids or other hazardous substances are to be located inboard of an appropriate damage penetration zone, but in no case less than 760 mm inboard of the moulded line of shell plating. Cofferdams may require to be arranged at the boundaries of tanks containing hazardous substances.

1.5.4 Adequate means are to be provided for the protection of ship steelwork in the event of spillage of liquefied gases and/or acid leakage.

1.5.5 Access to machinery or accommodation spaces is to be from a safe area.

1.6.1 For the purpose of longitudinal strength, the ship will be regarded as a Category 2 ship, as defined in Pt 3, Ch 4 Longitudinal Strength of the Rules for Ships.

1.6.2 Decks and other structure supporting machinery, tanks and plant, etc. are, in general, to comply with the requirements of Pt 3 Ship Structures (General) of the Rules for Ships. Such structure can, however, be considered on the basis of an agreed uniformly distributed loading in association with local loads at plant support points.

1.6.3 Where the nature and disposition of heavy equipment items are such that forces on the ship and support structure due to ship motions are significant, calculations of the loading and the structural response are to be submitted.

1.7.1 Tank and pumping arrangements for the well stimulating system are not to be led from or located in machinery spaces or accommodation areas.

1.7.2 Where tanks or systems are located below deck or in other enclosed compartments, the arrangements are to be such that well stimulation operations can be controlled from a safe location above the weather deck which is outside the compartment in which the tanks or system are located, see Ch 1, 1.5 Ship arrangements 1.5.2.

1.7.3 The requirements are to be in accordance with the relevant Rules as indicated in Part 5, Pt 5, Ch 12 Piping Design Requirements Pt 5, Ch 13 Ship Piping Systems Pt 5, Ch 14 Machinery Piping Systems Pt 5, Ch 15 Piping Systems for Oil Tankers of the Rules for Ships as applicable.

1.7.4 Carriage of acids:

1. Proposals for lining mild steel piping systems with corrosion-resistant materials (e.g. rubber) are to be submitted for consideration, together with full particulars of the proposed lining material, application procedures, post-application treatment and record of service. Attention is drawn to the high standards of material quality and workmanship required to ensure fault-free application.

2. Flanges of the loading and discharge manifolds are to be provided with shields, which may be portable, to guard against the danger of the medium being sprayed. In addition, drip-trays are to be provided to guard against leakage on to the deck.

3. Provision is to be made for suitable apparatus to detect leakage of medium into adjacent spaces.

4. Pump room pumping and drainage arrangements are to be independent of other piping systems and of approved corrosion-resistant materials.

1.8.1 Electrical equipment located in hazardous areas is to be of a certified safe type suitable for the gases and vapours involved.

1.8.2 Where a dynamic positioning system is to be provided the requirements of Pt 7, Ch 4 Dynamic Positioning Systems of the Rules for Ships are to be complied with.

1.9.1 The requirements of Pt 6, Ch 4 Fire Protection, Detection and Extinction Requirements of the Rules for Ships are to be complied with so far as they are applicable. Additional fire safety measures may be required if the well stimulation installation can be shown to present a special fire hazard.

1.10.1 Information regarding the safe operation of the ship under well stimulation operating conditions is to be provided onboard.

1.11.1 Suitable protective equipment, including eye protection, is to be provided for protection of crew members engaged in handling operations of well stimulation substances, taking into account the character of the substances.