Figure 2. Schematic of high pressure CO₂ fire extinguishing system used on vessel.
Figure 3. Schematic of low pressure CO₂ fire extinguishing systems used on vessel.

Potential Hazards:

• Accidental discharge of fire extinguisher.
• Miscommunication and coordination with:
  
• Ship owner and prime contractor
• Prime contractor and subcontractor

Requirements and Example Solutions:

• When active fixed extinguishing systems could create a dangerous atmosphere in vessels and vessel sections: [1915.506(a)]
  • Physically isolate the system or use other positive means to prevent the systems' discharge. [1915.506(b)(1)]
  • Ensure that employees are trained to recognize: [1915.506(b)(2)]
    • Systems' discharge, evacuation alarms and appropriate escape routes. [1915.506(b)(2)(i)]
    • Hazards associated with the extinguishing systems and agents including the dangers of disturbing system components and equipment (such as piping, cables, linkages, detection devices, activation devices, and alarm devices). [1915.506(b)(2)(ii)]
• During sea and dock trials, all systems must remain operational. Ensure that: [1915.506(c)]
  • All doors, hatches, scuttles, and other exit openings remain working and accessible for escape in the event that the systems are activated. [1915.506(d)(1)]
  • All inward opening doors, hatches, scuttles, and other potential barriers to safe exit are removed, locked open, braced, or otherwise secured. [1915.506(d)(2)]
• When testing a fixed extinguishing system, all workers must be evacuated from the space during discharge. Oxygen level must be tested to ensure safe conditions prior to workers reentering the space. [1915.506(e)]
• Fixed extinguishing system must be physically isolated before conducting maintenance on the system. [1915.506(f)]
• When fixed manual extinguishing systems are used to provide fire protection for spaces in which work must be performed, ensure that:  [1915.506(g)]
  • Only authorized workers are allowed to activate the system. [1915.506(g)(1)]
  • Authorized workers are trained to operate and activate the systems. [1915.506(g)(2)]
  • All workers are evacuated from the protected spaces, and accounted for, before the fixed manual extinguishing system is activated. [1915.506(g)(3)]

Figure 4. Activating mechanism for halon extinguishing system.

• When a fire extinguishing system is active:
  • Post signs at gangway and space. 
  • Provide emergency escape respirators should be provided.
  • Maintain a sign in and out log.
• Lock and tagout when working on the system. 
• Evaluate and assess hazards of halon used in the extinguishing system (Figure 4).
• Sample Fire Safety Plans. Shipbuilders Council of America, (2006).