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Be alarmed by all alarms

The USCG has published the following marine safety alert regarding the possible consequences of failing to take proper actions when faced with alarm signals from equipment. Recently, Coast Guard marine inspectors experienced two different circumstances involving the alarm and control system of steering gear on board relatively new vessels.

The USCG safety alert notes:

“Although neither event resulted in a marine casualty, they serve as a reminder to the potentially dangerous results that may occur when an alarm system is deliberately ignored. A false sense of operational safety develops when crewmembers continually silence what they consider to be a “nuisance alarm,” enabling a false perception of normalcy to develop.

Inspectors observed on two vessels that repetitive alarms occurred every time crewmembers performed steering tests that attempted to move the rudder through its range of motion. The alarms indicated that “hydraulic lock” events had occurred. Each time, the alarm was simply acknowledged by the crew and the steering gear adequately moved the rudder. However, no further investigation was conducted to identify the cause of the alarm.

It is well known that close calls and near misses occur more frequently than actual incidents. In this instance, the systems and alarms forewarned the operators of a problem. By ignoring the alarms, the crewmembers accepted a higher level of risk and reduced their safety margins. If the situation had been allowed to persist indefinitely, an unwanted incident could have occurred with potentially dire consequences.

As the result of these events, the Coast Guard strongly recommends that owner and operators ensure the following:

  • address the management of nuisance alarms in Safety Management Systems (SMS) and require immediate correction of their specific causes; and
  • Include strict prohibitions against the pinning or securing of alarm acknowledgment buttons and switches. Such actions should be deemed as unacceptable corrective measures as they have contributed to serious marine casualties in the past.
    This safety alert is provided for informational purpose only and does not relieve any domestic or international safety, operational, or material requirements.”

This USCG safety alert 16-16 can be downloaded from

Members may wish to review the following similar incidents (search words: alarm, ignored):

Safety Event

Published: 29 November 2016
Download: IMCA SF 32/16

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