Bridge Watch Alarm

The MS 421B Bridge Navigational Watch Alarm System (BNWAS) guards you from the duty officer unintentionally falling asleep. By demanding action regularly, alertness is guaranteed and chances for accidents are reduced.
New regulation’s from IMO’s Maritime Safety Committee (MSC) will require a BNWAS complying with IMO performance standards. The MS 421B is type approved according to the current legislation for Bridge Navigational Watch Alarm Systems, as laid down by the IMO in resolution 128(75) and IEC 62616.

Communication to VDR is integrated and the autopilot can also be connected to the BNWAS. The system can be expanded with remote reset buttons and PIR’s. A selection unit is also an option to regulate the different officers on duty. The optional units are small and easy to install.

The MS 421B is type approved to be used on all kinds of ships.



  • Everything that is needed according to IMO 128(75) in one single housing
  • Communication interface to VDR and ECDIS (NMEA)
  • Extendable by means of extra reset buttons
  • Reports to the officer’s cabins
  • Cost-reducing in installation
  • No disturbing lights, due to the dimming function
  • Possibility to switch on automatically together with the automatic pilot
  • The MS-421B is type approved to be used on all kinds of ships.


  • Dimensions 144x72X100 (HxWxD)
  • Cut out 138x68 (HxW)
  • Power supply 18-28 Vdc
  • Current 180mA max
  • 4 potential free outputs
  • Autopilot input
  • Reset input
  • Lloyd’s Register Type approved
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Sales Manager

Stefan Meun-Visser
+31 527 687 953 / +31 613 738 776

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