Bridge Navigational Watch Alarm System or BNWAS is an automatic alarm system that is used to monitor bridge activity and awareness of the Officer of the Watch (OOW) in order to avoid maritime accidents. If the OOW falls asleep or becomes otherwise incapacitated, the system sounds a series of alarms in order to alert other members of the crew, resulting in enhanced safety.
BNWAS was made mandatory by the International Maritime Organization (IMO) with amendments to SOLAS Chapter V Regulation 19 and adopted on June 5, 2009 by Resolution MSC.282(86).
The performance standards for a bridge navigational watch alarm system, as outlined in MSC.128(75), state the need for BNWAS as follows:
“The purpose of the bridge navigational watch alarm system (BNWAS) is to monitor bridge activity and detect operator disability which could lead to marine accidents. The system monitors the awareness of the Officer of the Watch (OOW) and automatically alerts the Master or another qualified OOW if for any reason the OOW becomes incapable of performing the OOW’s duties. This purpose is achieved by a series of indications and alarms to alert first the OOW and, if he is not responding, then to alert the Master or another qualified OOW. Additionally, the BNWAS may provide the OOW with a means of calling for immediate assistance if required. The BNWAS should be operational whenever the ship’s heading or track control system is engaged, unless inhibited by the Master.”
Followed by a collision of KAREN DANIELSEN with the Great Belt West Bridge, the Bahamas Maritime Authority and the Danish Maritime Authority jointly submitted a proposal to the UN’s International Maritime Organization (IMO), highlighting the need to make it mandatory for vessels to install and use a bridge navigational watch alarm system.
While installing BNWAS is mandatory, it is important to check the functionality of the equipment before installing it in a vessel.