Accidental Release of CO2 System
USCG stresses importance of design and testing of emergency system controls
The U.S. Coast Guard (USCG) issued a safety alert to remind shoreside and vessel personnel of the importance of designing and maintaining emergency systems to be logical and easily operated in high stress situations. The alert also stressed the importance of maintaining a high level of crew familiarity with emergency systems, as well as exercising safeguards during testing to mitigate the risk of human error or system malfunction. Although regulations prescribe standards for safety systems aboard vessels, installations particularly those onboard uninspected vessels, can vary dramatically.
During a recent Uninspected Towing Vessel (UTV) exam, a vessel crewmember intending to test the fuel oil shut-off cables instead pulled the CO2 system release cables. The emergency control panel used during the incident contained pull cables for both the CO2 system and fuel oil shut-offs.
Accidental releases are not uncommon and vessel crewmember and Coast Guard inspector fatalities have occurred in the past. Fortunately, in this instance the audible alarm system and release time delay functioned as intended, allowing all personnel to safely evacuate the machinery spaces prior to discharge.
In a separate recent UTV examination, an inspector found two sets of remote emergency shutdowns with only one set operational. The original station (see image on the right) appears to be fully operational, but was not connected. The operational shutdowns were at a separate location.
Crew interactions with emergency systems often occur during periods of increased stress (e.g., a compliance exam, drill, or an actual emergency). System design, proper human engineering, labeling and detailed training will substantially reduce the risk of human error.
The Coast Guard said it recommends conducting a comprehensive pre-test meeting and simulated step-by-step “walk-through” between involved parties prior to actual testing of complex or potentially confusing systems. Operational controls should be implemented to maximize safety and reduce risk.
Furthermore, the Coast Guard reminded all maritime operators of the importance in performing regular vessel specific emergency drills and to ensure that all crewmembers have the proper knowledge, skills and abilities to respond to any potential emergency.
UTV regulations in 46 Code of Federal Regulations (CFR) 27.209 require all crewmembers to be familiar with the location and operation of engine room fuel-shutoffs and fire extinguishing equipment. All credentialed mariners are required by 46 CFR 15.405 to be familiar with firefighting and lifesaving equipment.