What is Bridge Navigational Watch & Alarm System (BNWAS)?

Navigating a giant vessel is not at all an easy job and when it comes to situations of emergency, wherein the navigational officer has to make some quick decisions, the safety of the entire ship and its crew depends on that officer.

This is when automated systems are extremely useful. BNWAS is one type of automated system used on ships. While the navigation of the ship is probably the most important aspect of delivering the cargo and the crew safely between two points, it must also be understood that the human component attached to navigation is open to errors and faults; with a sudden mishap with respect to the watchkeeper (sudden unavailability due to health reasons while on watch), the ship might be exposed to dangers and the BNWAS assists to tackle such a problem.

What is BNWAS?

Bridge Navigational Watch & Alarm System – BNWAS is a monitoring and Alarm system which notifies other navigational officers or master of the ship if the officer on watch (OOW) does not respond or he/she is incapable of performing the watch duties efficiently, which can lead to maritime accidents.

bridge
Image for Representation purpose only; Credits: wikimedia.org

The purpose of a 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 OOWís duties. This is achieved through a mix of alarms and indications which alert backup OOWs as well as the Master. BNWAS warnings are given in the case of incapacity of the watchkeeping officer due to accident, sickness or in the event of a security breach, e.g. piracy and/or hijacking. Unless decided by the Master only, the BNWAS shall remain operational at all times.

Why Ships Need BNWAS?

There have been many incidents in the past wherein ships have collided or grounded due to wrong decision or inefficiency in taking a decision at the correct time. If during an emergency situation, a navigational officer is not capable of handling that situation, it can lead to devastating scenarios. To avoid this BNWAS is installed on the bridge which acts similar to a dead man alarm in the engine room.

Credits: imo.org

A series of alert and alarm is first sounded by BNWAS in the Navigation Bridge to alert officer on watch. If there is no response to the series of alarms, then BNWAS will alert other Deck officers, which may include Master of the ship, so that someone can come out on the bridge and handle the situation and tackle the problem.

Operational Requirements of BNWAS
The BNWAS primarily has three modes of operation:

Automatic
Manual ON
Manual OFF
Alarms and Indications
Once the BNWAS is put into operation, the dormant period should be between 3 to 12 minutes. This dormant period is the time in which the BNWAS is active without giving any alarm and it only once the dormant period is over that the alarm is sounded and the alarm/indication is sounded and the reset function needs to be activated
Once the dormant period ends, a visual indication (first stage; flashing indication) must be activated indicating/demanding that the officer rest it, if available and active
If not reset within 15 seconds of the visual indication, an audible alarm is sounded (first stage)
If at the first stage the audible alarm is not reset, 15 seconds after the audible alarm, another audible alarm (second stage; sound should have its own characteristic tone or modulation intended to alert, but not to startle, the OOW) is sounded in the backup officer’s and/or Master’s cabin
If at the second stage the audible alarm is not reset, 90 seconds after it, another audible alarm is sounded (third stage; easily recognisable, indicates urgency, volume sufficient for it to be heard throughout the locations above and to wake sleeping persons) at the locations of further crew members capable of taking corrective actions
Except for passenger vessels, the second and third stage alarm can be combined to sound at all locations. If this is applied, the third stage alarm may be omitted
For very large vessels, sufficient time of up to 3 minutes must be accounted for the backup officer or the Mastre to the reach the Bridge to tend to the situation
The Reset Function
Reset can only be done from physically located areas of the bridge providing proper look out
Reset can be only be done with a single operator action (for those familiar with BNWAS, one stroke to the round reset switch) which starts the dormant period further, cancelling the alarms/indications
Constant activation of the dormant period vis a vis the reset button should not extend the dormant period to more than that is set or bring about any suppression of the alarms/indications
Additionally
An “Emergency Call” feature must be present to immediately skip to the second and third stage alarms. This is present for the OOW to summon immediate assistance
Accuracy of the BNWAS should be within the window of 5% or 5 seconds, whichever 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 power supply. The malfunction indication, and all elements of the Emergency Call facility should be powered from a battery maintained supply
Outputs should be available for integration with other bridge equipments if need be
Regulations for BNWAS
SOLAS Chapter V Regulation 19 states:

Cargo ships of 150 gross tonnage and upwards and passenger ships irrespective of size constructed on or after 1 July 2011
Passenger ships irrespective of size constructed before 1 July 2011, not later than the first survey after 1 July 2012
Cargo ships of 3,000 gross tonnage and upwards constructed before 1 July 2011, not later than the first survey after 1 July 2012
Cargo ships of 500 gross tonnage and upwards but less than 3,000 gross tonnage constructed before 1 July 2011, not later than the first safety survey after 1 July 2013
Cargo ships of 150 gross tonnage and upwards but less than 500 gross tonnage constructed before 1 July 2011, not later than the first survey after 1 July 2014
A BNWAS installed prior to 1 July 2011 may subsequently be exempted from full compliance with the standards adopted by the organization, at the discretion of the Administration

Introduction to Global Maritime Distress Safety System (GMDSS)

During the 18th century, the ships sailing in international and coastal waters were dependent on the Morse code to send any kind of distress signal to a coastal authority or ships in the nearby vicinity during emergency. Since it was a transmission of texture information using tones or lights, this kind of message was never very clear to understand what kind of emergency is there on board ships. Therefore, an internationally agreed safety procedure was adopted by IMO under SOLAS chapter IV which is known as GMDSS- Global Maritime Distress Safety System.

GMDSS and its Uses

On 1st Feb 1999, the fully implemented GMDSS came to picture. It was a set standard for usage of communication protocol, procedures and safety equipment to be used at the time of distress situation by the ship. Under GMDSS, all the passenger ships and cargo ship above 300 GT involved in the voyages in international waters have to carry equipment as per GMDSS.

When a ship uses GMDSS, it basically sends a distress signal via a satellite or radio communicationequipment. It’s also used as a medium for sending or receiving maritime safety information and general communication channel.

In the GMDSS framework, there are different Sea Areas to allot the working equipment in the respective area. They are as follows:

AREA RANGE EQUIPMENT
A1 20 to 50 M VHF DSC
A2 50 to 400 M VHF + MF
A3 70° N to 70° S VHF + MF + One INMARSAT
A4 Above 70° N or S HF + MF + VHF

To understand the above table further, following are the ranges with regard to the frequencies in a specific band:

Medium Frequencies: 300 KHz to 3 MHz
High Frequencies: 3 MHz to 30 MHz
Very High Frequencies: 30 MHz to 300 MHz
Very High Frequencies (VHF)
For the purposes of maritime communication, the range of 156 MHz to 174 MHz is allocated. Channel 16, which is set at 156.800 MHz, is for Distress, Urgency and Safety communication. Channel 70, set at 156.525 MHz, if for routine VHF DSC (Digital Selective Calling) watch.

GUARD channels are set put above and below Channel 16 to avoid any interference on Channel 16. One cannot have seamless traffic on Channel 16 with interference with regard to other communication aside from distress, safety and urgency. So the Guard channel frequencies are 156.775 MHz and 156.825 MHz.

Among other things, the VHF set runs on a 24 Volt DC supply with J3E type of transmission for Radiotelephony and G2B type of transmission for VHF DSC.

The different elements of GMDSS are as follows:
INMARSAT:  It is a Satellite operated system that includes ship earth station terminals – Inmarsat B, C and F77. It provides telex, telephone and data transfer services between ship-to-ship, ship to shore, and shore to ship along with a priority telex and telephone service connected to shore rescue centres.
NAVTEX: NAVTEX is an internationally adopted automated system which is used to distribute MSI-maritime safety information, and includes weather forecasts and warnings, navigational warnings, search and rescue notices and other similar safety information.
Emergency Position Indicating Radio Beacon (EPIRB): EPIRB is an equipment to help determine the position of survivors during a SAR operation. It is a secondary means of distress alerting. Read about EPIRB here.
Search and Rescue Locating Equipment: Primarily the Search and Rescue Radar Transponder. This is used to home Search and Rescue units to the position of distress which transmits upon interrogation. Read about Search and Rescue equipment here.
Digital Selective Calling (DSC): This is a calling service between ship to ship, ship to shore or vice versa for safety and distress information mainly on high or medium frequency and VHF maritime radio.
Documents to be carried onboard with regard to GMDSS:
Ship’s Radio License
Radio Operators Certificates
Safety Radio Certificate
GMDSS Radio Log Book
ITU List of Cell Signs and Numerical Identities of Stations used by Maritime Mobile and Maritime Mobile Satellite Services
ITU List of Coast Stations
ITU List of Ship Stations
ITU List of Radio determination and Special Service Stations
Antenna Rigging Plan
Valid Shore Based Maintenance Certificate
GMDSS Training
The handling of GMDSS equipment requires certified training as well as licensing from the Telecommunication department of the department. The General Operators Certificate (GOC) is mandatory in order for an officer to be allowed to handle GMDSS equipment onboard the ship.

To obtain this GOC, a short course is compulsory to attend following which an exam is conducted (written and oral), which needs to be cleared.  This training is aimed at Cadets who ought to become licensed Radio Operators to operate all the equipment in conjunction with the regulations laid out for GMDSS.

The training period is around 12 days and owing to the course being mandatory, it is advised to call in to an approved institute to book a seat for a future date, well in advance. Depending which country the individual is from, they must check the respective institute websites as well as the Ministry of Shipping (or whichever applicable for their country) website to get the full details on eligibility and criteria for admission into the GMDSS course.

Over the period of the course, the officer is taught about the various aspects of GMDSS ranging from Radio Log to sending IMNARSAT messages and all such aspects of it which will be required when carrying out communication onboard. The written exam tests the theory whereas the oral examination is a one on one session with a surveyor who tests the individual on the different aspects of GMDSS, covering the whole syllabus (theory as well as practical).

Recommended GMDSS Books:
GMDSS – A Guide For Global Maritime Distress Safety System

GMDSS – A User’s Handbook

Admiralty List of Radio Signals (ALRS) Volume 5: GMDSS
NP285 or ALRS Vol. 5 is the publication with extensive information in theory as well as practical use for all things pertaining to the GMDSS. Correction for this is found in Section 6 of the weekly Notices To Mariners (TNM). Its contents covers as follows:

Distress Communication And False Alert
Operation Procedure For Use Of DSC Equipment
Search And Rescue Transponder
Extract From ITU Radio Regulations
VHF DSC List Of Coast Stations For Sea Area A1
MF DSC List Of Coast Stations For Sea Area A2
HF DSC List Of Coast Stations For Sea Area A3
INMARSAT
Maritime Safety Information (MSI)
SafetyNet
NAVTEX
Distress, Search And Rescue
Portable Marine Radio
The portable marine radio or the survival craft transceiver, a very important element of the GMDSS, is a piece of equipment located in the bridge in case the ship’s personnel have to board the survival craft but they may be used for communication on board as well.

In case it’s used in emergency, it is used for on scene coordination between the survival craft and the search and rescue units. The IMO requirements for the survival craft transceivers are as follows:

Can be operated by unskilled personnel
Transmission and Reception on 156.8 MHz (Channel 16) and 156.3 MHz (Channel 6)
Withstand a drop of 1 meter
Watertight to a depth of 1 meter for 5 minutes
Minimum power of 0.25 watts
A power reduction switch available
The antenna must be omnidirectional and vertically polarized
Battery power capacity for 8 hours (Nickel Cadmium or Lithium Battery)
The scope of GMDSS is vast and extensive reading on it, through publications and manuals and all other available means, is the only way to get better at handling the equipments and gain further knowledge about the setup.

Being a mandatory setup onboard ships which is also the key setup with regard to emergency situations, it is actually in self interest for the ship’s officer to gain maximum knowhow on every aspect of the GMDSS.

Disclaimer: The authors’ views expressed in this article do not necessarily reflect the views of Marine Insight. Data and charts, if used, in the article have been sourced from available information and have not been authenticated by any statutory authority. The author and Marine Insight do not claim it to be accurate nor accept any responsibility for the same. The views constitute only the opinions and do not constitute any guidelines or recommendation on any course of action to be followed by the reader.

What standards are required for Navigational Bridge  Equipment?

SOLAS-Regulation 18 – Approval, surveys and performance standards of navigational systems and equipment and voyage data recorder
This exploration of the safety of navigation section of SOLAS now looks at the performance standards required for ship’s bridge equipment. In addition to a quick look at the regulation 18 the post also provides a set of links to the related resolutions containing the standards.

What does Regulation 18 require?
That systems and equipment required to meet the requirements of regulations 19 and 20 shall be of a type approved by the Administration and  Systems and equipment installed on or after 1 July 2002 to perform the functional requirements of regulations 19 and 20 shall conform to appropriate performance standards not inferior to those adopted by the Organization.

What must you ensure if bridge equipment is installed of replaced?
That  the requirements of Regulation 18 are met.

UK MCA table of IMO performance standards

The IMO Standards

I have used the UK table of IMO performance standards list the resolutions and whenever possible linked across to the sources of the document. Some of these links are to IMO pages, others to National Authority web pages.

General

IMO index of resolutions
A.694(17)– General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
A.813(19)-General requirements for Electromagnetic Compatibility (EMC)
Intergration
Integrated Bridge Systems (IBS)
MSC.64 (67) Annex 1 -Adoption of new and amended performance standards.
A.694 (17)– General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Integrated Navigation Systems (INS)
MSC.86 (70) Annex 3-Adoption of new and amended performance standards for Navigational equipment.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.

Direction Compasses – Magnetic Compass

IMO A.382 (X)- Magnetic compasses carriage and performance standards
A.694(17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Gyro Compass
A.424 (XI)-Performance standards for gyro-compasses
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Gyro Compass- HSC
A.821 (19)–Performance standards for gyro-compasses for high-speed craft
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Display of direction information
Gyro Compass Heading Repeater
A.424 (XI)-Performance standards for gyro-compasses
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Gyro Bearing Repeater
A.424 (XI)–Performance standards for gyro-compasses.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Transmitting Heading Device (THD)
MSC.116(78)– Application of performance standards for Transmitting Heading Devices (THDs) to Marine Transmitting Magnetic Heading Devices (TMHDs)
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Transmitting Magnetic Heading Device (TMHD)
MSC.86 (70) ANNEX 2-Adoption of new and amended performance standards for Navigational equipment.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
SC.116(78)– Application of performance standards for Transmitting Heading Devices (THDs) to Marine Transmitting Magnetic Heading Devices (TMHDs)
Rate of Turn Indicator
A.526 (13)– Performance standards for rate of turn indicators
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids

Control

Automatic Pilots
A.342 (IX)-Recommendation on performance standards for automatic pilots.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Track Control Systems
MSC.74 (69) annex 2- Adoption of new and amended performance standards
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Automatic Pilots for HSC
A.822 (19)–Performance standards for automatic steering aids (automatic pilots) for high-speed craft
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Distance
Speed and Distance Measuring Equipment (SDME)
A.478 (XII) –Performance standards for devices to indicate speed an distance
A.824(19)-performance standards for devices to measure speed and distance
MSC.96(72)- Adoption of amendments to performance standards for devices to measure and indicate speed and distance
Echo Sounder
A.224 (VII) –Performance standards for Echo-Sounding equipment
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.Position

Electronic charts
ECDIS Standard
A.817 (19) -Performance standards for Electronic Chart Display and information systems (ECDIS)
A.232(82)-Adoption of revised performance standards for Electronic Chart Display and information systems (ECDIS)
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Back up requirements
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
MSC.64(67) annex 5- Adoption of new and amended performance standards.
RCDS mode of operation
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
MSC.86(70) annex 4-Adoption of new and amended performance standards for Navigational equipment.
Electronic Navigation Systems
Global Navigation Satellite System Receiver (GNSS)GPS
A.819 (19)
Now

MSC.112(73)-Adoption of the revised performance standards for shipborne global positioning system (GPS) receiver equipment.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
GLONASS
MSC.53 (66)-Performance standards for shipborne GLONASS reciter equipment.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
DGPS / DGLONASS
MSC.64 (67) annex 2-Adoption of new and amended performance standards.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
MSC.114(73) -Adoption of the revised performance standards for shipborne DGPS and DGLONASS Maritime Radio Beacon Receiver equipment
Combined GPS/GLONASS
MSC.74 (69)-Adoption of new and amended performance standards
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Electronic Position Fixing Systems
Worldwide radio navigation system
A.815 (19)-Worldwide Navigation System.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Accuracy standards for navigation
A.529 (13)-Accuracy standards for Navigation
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Differential OMEGA
A.479 (XII) -Performance Standards for shipborne receivers for use with differential Omega.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
LORAN-C and CHAYKA
A.818 (19)-Performance standards for shipborne LORAN-C and chayka receivers
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.

Detection

Radar
Consolidated performance standards for all new Radar Equipment (1/7/2008 and after)

MSC.192(79) -Adoption of the revised performance standards for Radar Equipment
Radar Equipment
Before 01/09/1984

A.222 (VII) -Performance standards for Radar Navigational Equipment
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Between 01/09/1984 and 31/12/1998

A.477 (XII)-Performance standards for Radar Equipment
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
On or after 01/01/1999

MSC.64(67) Annex 4-Adoption of new and amended performance standards.
Radar Equipment for HSC
A.820 (19)– Performance standards for navigational equipment for high speed craft.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Radar- Symbols for Controls
A.278 (VIII)–Supplement on performance standards for navigational radar equipment
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Plotting
Automatic Radar Plotting Aid (ARPA)
A.422 (XI)-Performance standards for Automatic Radar Plotting Aids (ARPA)
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Electronic Plotting Aid (EPA)
MSC.64 (67) Annex 4-Adoption of new and amended performance standards.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Automatic Tracking Aid ATA
MSC.64 (67) Annex 4-Adoption of new and amended performance standards.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Enhancing
Radar Reflector
A.384 (X)-Performance standards for Radar Reflectors
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
MSC.164(78)-Revised performance standards for Radar Reflectors
Radar Beacons & Transponders
A.615 (15)–Radar beacons and transponders
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
SARTS
A.802 (19)-Performance standards for Survival Craft Radar Transponders for use in Search a Rescue operations
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids

Awareness
Automatic Identification System (AIS)
MSC.74 (69) annex 3

A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.

Lookout
Sound Reception System
MSC.86 (70)-Adoption of new and amended performance standards.
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Night Vision Equipment
MSC.94 (72)-Performance standards for night vision equipment for High-Speed Craft (HSC)
A.694-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Signalling Lamps
MSC.95 (72)-Performance standards for daylight signalling lamps
Recording
Voyage Data Recorder (VDR)
A.861 (20)-Performance standards for Shipborne Voyage Data Recorders (VDRs)
A.694 (17)-General Requirements for Shipborne Radio equipment forming part of the GMDSS and for electronic navigation aids.
Simplified Voyage Data Recorder (S-VDR)
MSC.163(78)-Performance standards for Shipborne Simplified Voyage Data Recorders (VDRs)