Investigations & Casualty Analysis

12/20/2017: Safety Alert 13-17 – Fixed CO2 fire extinguishing systems

The Office of Investigations and Casualty Analysis released Safety Alert 13-17, “Fixed CO2 Fire Extinguishing Systems: When your hoses aren’t right you might lose the firefight,” to remind mariners of the proper positioning and maintenance for fixed CO2 fire extinguishing systems.

Recently, Coast Guard marine inspectors discovered critical deficiencies onboard a containership with its fixed CO2 fire extinguishing system. The conditions
associated with the CO2 system may have prevented the system from operating correctly or, if not discovered, the system may not have operated at all in an
emergency situation.

During the inspection, it was noted that some of the hoses which connected the large CO2 cylinders to the manifolds were wrapped around the bottle valve handles as shown in photographs A and B.

Photos of cylinders with hoses wrapped improperly around bottle vale handles.

The bottles could have been in place for a long period of time, in their original positions without regard to the stresses placed on the connecting hoses. However, experts in Fixed CO2 System Servicing have indicated that service personnel routinely find loose bottles that have rotated over a period of time. The experts expressed that photographs A and B represented extreme cases of rotation. The service personnel also stated that “four bottle deep” manifold systems were atypical and may have contributed to an inability to maintain tightness.

These bottles should have been clamped tightly in place by the use of wooden brackets as displayed in photograph C. Wooden spacers in between the rows of bottles can also be used to ensure proper securing of all the bottles.

Photos of blottles clamped properly in place by use of wooden brackets.

Inspectors also found significant cracking of the CO2 discharge hoses which were under tension as shown in photograph D. This condition is known as ozone cracking and occurs when very small amounts of ozone in the atmosphere interact with the polymers that compose rubber products and certain other elastomers when those products are under tension.

Photo of significant cracking of the CO2 discharges hoses stored under tension.

As a result of the inspection the vessel was detained until these and other identified deficiencies identified were corrected. During a re-inspection of the vessel to clear the deficiencies, it was discovered that the servicing organization that replaced the hoses, installed several new hoses in a similar orientation that maintained excessive stress on the hoses. That issue was subsequently rectified by rotating the bottles.

The Coast Guard strongly recommends that vessel owners and operators obtain MSC.1/Cir.1318 for distribution to their fleets. In addition, each vessel’s Safety Management System should incorporate the Circular’s pertinent data. Public users can establish a free account to access the Circular and other important information at The Coast Guard also urges owners and operators to ensure the following steps are taken for each fixed CO2 system:

• Bottle installation must be accomplished carefully considering hose and actuator positioning in addition to ensuring stress is minimized for each hose. Securing devices must be inspected for effectiveness.

• Vessel crewmembers should check for bottle rotation, loose bottles, and excessive stress on discharge hoses during periodic inspections of fixed CO2 systems. All appropriate safety precautions should be completed prior to taking any actions to re-secure or reposition CO2 cylinders.

Read Safety Alert 13-17 for full details.

This blog is not a replacement or substitute for the formal posting of regulations and updates or existing processes for receiving formal feedback of the same. Links provided on this blog will direct the reader to official source documents, such as the Federal Register, Homeport and the Code of Federal Regulations. These documents remain the official source for regulatory information published by the Coast Guard.

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