Under SOLAS Chapter II-2 (Regulation 10.5.6), FSS Code (Chapter 7), and IMO MSC/Circ.1165, all passenger ships and cargo vessels of 2,000 GT and upwards must be fitted with an approved Fixed Local Application Fire-Fighting System (Water Mist / Hyper-Mist). Protecting high-risk machinery areas (main engine cylinder tops, purifiers, boiler burners, and incinerators), water mist rapidly extinguishes fires without requiring engine room evacuation or space shutdown.
Engineering Overview & Table of Contents
- 1. Regulatory Standards: SOLAS II-2/10 & FSS Code Chapter 7 Mandates
- 2. High-Pressure Pump Skids: Multi-Stage Centrifugal Pumps & Unloaders
- 3. Micro-Droplet Physics: Evaporative Cooling, Oxygen Displacement & Radiant Heat
- 4. Deluge Section Solenoid Valves, Stainless Steel Piping & Nozzle Descaling
- 5. Automated Fire Detection Interlocks: Dual Optical Flame & Smoke Matrix
- 6. Statutory Class Annual Surveys Across UAE Ports
1. Regulatory Standards: SOLAS II-2/10 & FSS Code Chapter 7 Mandates
Unlike total flooding CO2 systems that require sealing the entire space and evacuating personnel, water mist local application systems can be discharged immediately while machinery continues running. Water mist systems must be capable of continuous discharge for at least 20 minutes across protected machinery zones. Seanav delivers certified Water Mist System Installation, Water Mist System Commissioning, and Water Mist System Maintenance across Marioff (HI-FOG), Semco / Danfoss Fire Safety (SEM-SAFE), Tyco / Johnson Controls (AquaMist), Minimax, and FIFI4MARINE systems.
2. High-Pressure Pump Skids: Multi-Stage Centrifugal Pumps & Unloaders
Water mist systems generate micro-droplets under high hydraulic pressures (typically 80 to 140 bar):
High-Pressure Water Mist Skid Servicing:
- Multi-Stage Stainless Steel Pumps: Overhauling axial piston pumps or high-pressure multi-stage centrifugal pumps (Grundfos / Danfoss PAHT); inspecting ceramic plungers and carbon-graphite mechanical seals.
- Pressure Unloader & Relief Valves: Testing system pressure regulating valves (set at 120–140 bar) and unloader bypass circuits to return excess flow to water break tanks.
- Pneumatic Jockey Pump: Overhauling low-flow jockey pumps maintaining standby line pressure (approx. 10–12 bar) to ensure immediate water delivery upon solenoid valve opening.
- Potable Water Break Tank & Filtration: Cleaning 316L stainless steel storage tanks, replacing 10-micron duplex water filters, and verifying automatic fresh water makeup float valves.
3. Micro-Droplet Physics: Evaporative Cooling, Oxygen Displacement & Radiant Heat
High-pressure mist nozzles atomize water into ultra-fine droplets (Dv90 < 100 microns). Upon entering the flame zone, the massive surface area causes flash evaporation into steam (expanding 1,700 times), which simultaneously cools the combustion zone, displaces oxygen locally, and attenuates thermal radiation.
4. Deluge Section Solenoid Valves, Stainless Steel Piping & Nozzle Descaling
Protected machinery zones are isolated by section solenoid valves:
| Protected Zone | Component | Seanav Service Scope |
|---|---|---|
| Main Engine Top | Section Solenoid & Nozzles | Ultrasonic cleaning micro-nozzles; clearing mineral scaling; testing 24V DC section valve release. |
| Auxiliary Diesel Generators | Dedicated generator enclosure misting | Testing manual release pushbuttons located locally outside the generator flat and in the ECR. |
| Purifier & Boiler Burners | High-risk oil mist zones | Verifying nozzle spray angles fully envelope purifier sludge chutes and burner fronts. |
5. Automated Fire Detection Interlocks: Dual Optical Flame & Smoke Matrix
To avoid false water damage, automated discharge requires cross-zoned coincidence detection: simultaneous activation of an optical IR/UV flame detector and an optical smoke detector in the same zone automatically starts the main mist pump and opens the zone section valve within 20 seconds.
6. Statutory Class Annual Surveys Across UAE Ports
Seanav provides turnkey water mist inspections, flow trials, nozzle replacements, and Class survey documentation across Kandla, Mundra, Mumbai, JNPT, Cochin, Chennai, Paradip, and Visakhapatnam.
Schedule High-Pressure Water Mist Survey or Pump Skid Overhaul
Read detailed water mist engineering procedures on our Active Fire Protection & Water Mist Hub or book an engineering visit at any Indian Commercial Port.