QUESTION 4.1.5

Bridge navigational watch alarm system

Oil, Chemical, LPG, LNGBridge

What is being checked

The inspector is checking whether BNWAS provides an active vigilance check whenever the vessel is underway and at other company-required times, with protected settings and reliable escalation, with officers able to configure, cross-check, test and respond to failure of the actual equipment fitted.

Ready onboard

0/6 complete

PROCEDUREThe company procedure defines safe use, testing, limitations and failure response for bridge navigational watch alarm system.CONFIGURATIONThe system is in the required operating mode, the first-stage interval is correctly set and access to mode or timing controls is restricted as approved.FUNCTION TESTTest the reset devices, visual warning, bridge audible alarm, officer and crew accommodation escalation, failure indication and power supply.RESET POINTSReset devices are positioned so deliberate bridge activity is required and none is defeated or held active.ESCALATIONSecond and third stages reach the Master's or officers' and crew locations required by the installation.ANCHOR POLICYUse at anchor follows company requirements and the actual anchor-watch risk.

Practice questions

Answer aloud, then open the preparation point.

1What safety function does bridge navigational watch alarm system provide?

Bnwas provides an active vigilance check whenever the vessel is underway and at other company-required times, with protected settings and reliable escalation.

2How is the complete function tested?

Test the reset devices, visual warning, bridge audible alarm, officer and crew accommodation escalation, failure indication and power supply.

3What is its principal limitation?

Automatic reset from movement or routine activity can create false assurance if it does not represent deliberate OOW acknowledgement.

4What is your response if it fails?

Maintain a strengthened watch, notify the Master, record and repair the defect, and use the approved alternative vigilance control until restored.

5Show the latest test and operational evidence.

Link the dated record to the actual unit, test method, result, defect response and restoration; a panel lamp test alone is not sufficient where the full signal path can be tested.

Where an observation may arise

PROCEDURE UNKNOWN

The responsible officer cannot explain safe use, limitations or failure response.

TEST INCOMPLETE

Testing does not prove the required operational function or remote indication.

SWITCHED OFF

BNWAS is not operating during a period when it is required.

UNAUTHORISED SETTING

Mode or interval is changed without Master's control.

FALSE RESET

A device or workaround continuously suppresses the vigilance sequence.

Master's practical note

Verify the final escalation point, not only the bridge buzzer. The system fails operationally if an incapacitated OOW does not bring another person to the bridge.

Equipment boundary and references

Equipment boundary: BNWAS requirements depend on ship construction and installation approval, while company policy may require broader use. It never permits a reduced lookout or inattentive watch.

References

OCIMF SIRE 2.0 Question Library Part 1, Version 1.0, Question 4.1.5
SOLAS Chapter V regulation 19
IMO Resolution MSC.128(75)
ICS Bridge Procedures Guide

Last reviewed: 2026-09-11