Monday, 21 March 2011

MPA Singapore Rule Out Use of Motion Sensors on BNWAS for Their Vessels

The Maritime and Ports Authority of Singapore has clarified the issue of use of motion sensors as a method of confirming OOW activity to reset a BNWAS on Singapore registered vessels.

MPA Singapore has taken a similar viewpoint to Lloyd’s Register in that they do not see motion sensors as providing an indication of the awareness of the Officer of the Watch (OOW).

MPA Singapore state:
“A motion sensor would not meet the design criteria for reset function in accordance with MSC.128(75). As stated in paragraph 6.2.2, "Reset devices should be designed and installed so as to minimise the possibility of their operation by any means other than activation by the OOW.
In the case of BNWAS, the OOW may not be the only trigger for the motion sensors, in particular, in consideration that the ship is moving, and in rough seas the rolling could be severe, resulting in curtains swaying, falling objects in bridge, etc, all which may trigger the motion sensors. Also, having motion sensors would add an additional device to the alarm system, which would then require testing and approval that they can function properly in a shipboard environment as part of the alarm system.
The intent is also clearly stated in the above para 6.2.2, that the activation by the OOW positively is preferred, not via a passive means such as motion sensors. The resolution also actually provides an example of where the reset button could be located, eg chart table or ECDIS, where the OOW would be for considerable periods of time and therefore could easily reach out to reset the alarm. The aim is to include simple reset devices which would not be prone to false resets or failure and for the OOW to have complete awareness of the need to actively reset the alarm. Motion sensors will take away this awareness.
Please refer to our shipping circular no. 21 of 2010 on BNWAS.”

Navgard™ - Lloyd’s Register (LR) Type Approved BNWAS

The LR Type Approved version of the Navgard™ BNWAS has been designed and approved to operate without the use of motion sensors. Instead, the system operates with manual push buttons to reset the BNWAS at the prescribed intervals to meet with LR requirements.

The criteria that the systems meets for Lloyd’s Register Type Approval also means that it is ideal to meet the requirements of the Singapore MPA.

Find out more about Navgard LR Type Approved BNWAS.


  1. Intelligent surveillance systems based on automated analysis of human motion has been one of the most active research topics in computer vision in recent years.
    So it seems to be a very conservative standpoint of MPA preserving the “reset switch” as the only acceptable intepretation of "means for monitoring human awarenes"s, as the IMO has put it in resolution MSC.128(75).

    Olaf Gundersrud/Nautical Surveyor

  2. Location of reset button should not be placed in chart room or radio room from where watch keeper may do the paper work or chart corrections and reset the BNWAS without proper navigation. Purpose of the equipment will be in vain.


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