Scope of Work

• Modeled the most remote area (C-Deck) for hydraulic demand verification of the accommodation sprinkler system.

• Classified accommodation spaces as Light Hazard with wet-pipe sprinklers and verified deck-wise distribution.

• Performed head-loss and pressure checks across DN25–DN80 distribution, vertical risers, and sectional isolation/testing valves.

• Prepared isometric and deck plans with nozzle counts and main riser routing for all protected decks.

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Design Basis

• System type: Wet-pipe sprinkler system (Accommodation)

• Remote area: C-Deck

• Occupancy: Light Hazard

• Design density: 0.10 gpm/ft² over 1,500 ft²

• Sprinklers: K5.6, Standard Response, pendent; max. 225 ft²/head (calc basis used ~156.3 ft²/head spacing)

• End-head minimum pressure: Using Q=KPQ = K\sqrt{P}Q=KP​ → 15.63 gpm @ 7.79 psi per end sprinkler

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Hydraulic Demand Highlights

• Remote-area base flow: 1,500 ft2×0.10=150 gpm1,500\ \text{ft}^2 \times 0.10 = \mathbf{150\ gpm}1,500 ft2×0.10=150 gpm (≈ 10 operating sprinklers × 15.63 gpm).

• End sprinkler (calc start): 15.63 gpm @ 7.79 psi.

• Network: DN25 branches, DN32/50/65 distribution, DN80 mains and risers as shown on isometric; flushing/test take-offs provided per deck.

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Protected areas (sample counts):
Bridge Deck – 15 nozzles | Forecastle – 30 | A-Deck – 68 (plus 6 @ 141 °C) | B-Deck – 62 | C-Deck – 69 | Main Deck – 33.

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Fire Pump & Controls

• Sprinkler Main Pump: 100 m³/h @ 7 bar (≈ 440 gpm @ ~102 psi)

• Jockey Pump: 3 m³/h @ 7 bar (≈ 13 gpm @ ~102 psi) for pressure maintenance

• Water sources: Sprinkler tank connections with sea-chest and sanitary system supply provisions; sectional isolation, non-return, and test/globe valves per deck for testing & rinsing.

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Materials, Testing & Class

• Pipe: Carbon steel seamless, hot-dip galvanized (ANSI A106 Gr.B / GB5312).

• Valves & fittings: PN10 flanges, graphite gaskets (asbestos-free), AISI 316 internals, brass nameplates.

• Pressure regime: Working/design to 10 bar; workshop hydrotest to 15 bar; onboard testing per ABS (≥1.25× working).

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Deliverables

• Hydraulic calculation sheets (remote area, node-by-node losses, residuals).

• Isometric & deck plans marking risers, sectional valves, test points, and nozzle schedules.

• Pump sizing note with duty curve alignment and jockey control philosophy.

• Submission pack for Class/AHJ: drawings, specs, and test procedures.

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Outcome

A compliant, class-ready sprinkler system for accommodation spaces that meets the Light-Hazard density, achieves minimum end-head pressure, and provides deck-wise testing and isolation—ensuring reliable fire protection across all occupied areas of the vessel.

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👉 View Design and Calculations.​​