BANWAS NOTES

 

 Bridge Navigational Watch and Alarm System

Purpose: To monitor bridge activity and detect operator disability which could lead to marine

accidents.

Alarm and Indication: Dormant period 3 to 12 minutes, the period where BNWAS is active without giving any alarm.Once dormant period ends, it gives visual indication ( First stage, flashing indication). If not reset within 15 seconds, audible alarm is sounded. ( first stage). If the first stage alarm is not reset in 15 seconds after audible alarm, another audible alarm ( second stage, sound should have its own characteristic tone or modulation intended to alert, but not to startle the officer on watch) is sounded in the backup officer’s cabin/ Master’s cabin. If the second stage alarm is not reset within 90 seconds, another audible alarm is sounded ( 3rd stage, easily recognizable, indicates urgency, volume sufficient for it to be heard throughout the locations above and to wake up sleeping persons). Expect for passenger ships, 2nd and 3rd stage alarm can be combined to sound to all locations. For large vessels, sufficient time up to 3 minutes are accounted for the back up officer or Master to reach bridge.

Reset Functions:

Reset can only be done from the physically located areas of the bridge providing proper lookout. Reset can only be done with a single operatoraction ( one stroke to the round reset switch) which starts the dormant period further, cancelling the alarm/ indications.

Additionally:

An “ Emergency Call” feature must be present to immediately skip to the second and third stage alarms. This is present for the Officer On Watch to summon immediate assistance. Accuracy of the BNWAS should be within the window of 5 % or 5 seconds, which ever is lesser. Operational mode and the duration of the dormant period setting shall be restricted to the Master only. To be powered from the main supply. The malfunction indication and all elements of emergency call facility should be powered from a battery maintained supply. Output be available for integration with other bridge equipments if need be. 

Regulations for BNWAS:

SOLAS Chapter V Regulation 19 states:

Cargo ship greater than 150 GRT and passenger ship irrespective of size constructed on or after 1st

July 2011.

Cargo ship of 3000 GRT and upward constructed before 1st July 2011 but not later than the first

survey after 1st July 2012.