Navigation Bridge Visibility

Navigation Bridge Visibility

2022-05-10     21:42

Ships of not less than 55 m in length (Overall Length) and constructed on or after 1 July 1998 shall meet the below requirement according to the SOLAS 2006 Amend / Chapter V / Reg. 22.

Ships constructed before 1 July 1998 shall, where practicable, meet the requirements of paragraphs 1 and 2. However, structural alterations or additional equipment need not be required.

Navigation Bridge Visibility-a

Figure 1

Navigation Bridge Visibility-b

Figure 2

  1. The view of the sea surface from the conning position shall not be obscured by more than two ship lengths, or 500 m, whichever is the less, forward of the bow to 10° on either side under all conditions of draught, trim and deck cargo; (See figure 2)
  2. No blind sector caused by cargo, cargo gear or other obstructions outside of the wheelhouse forward of the beam which obstructs the view of the sea surface as seen from the conning position, shall exceed 10 degrees. (See figure 1 & 3)

    A1, A4 ≤ 10◦

    The total arc of blind sectors shall not exceed 20 degrees.

    A1+A2+A3+A4 ≤ 20◦

    The clear sectors between blind sectors shall be at least 5 degrees.

    B1, B2, B3, B4, B5 ≥ 5◦

    However, in the view described in (1), each individual blind sector shall not exceed 5 degrees;

    A2, A3≤ 5◦

Navigation Bridge Visibility-c

Figure 3

  1. The horizontal field of vision from the conning position shall extend over an arc of not less than 225 degrees that is from right ahead to not less than 22.5 degrees abaft the beam on either side of the ship; (See Figure 1)
  2. From each bridge wing the horizontal field of vision shall extend over an arc at least 225 degrees that is from at least 45 degrees on the opposite bow through right ahead and then from right ahead to right astern through 180 degrees on the same side of the ship; (See Figure 1)
  3. From the main steering position the horizontal field of vision shall extend over an arc from right ahead to at least 60 degrees on each side of the ship;
  4. The ship's side shall be visible from the bridge wing;
    1. a view from the bridge wing plus a distance corresponding to a reasonable and safe distance of a seafarer leaning over the side of the bridge wing, which needs not to be more than 400 mm, to the location vertically right under the maximum beam of the ship at the lowest seagoing draught is not obscured; or
    2. the sea surface at the lowest seagoing draught and with a transverse distance of 500 mm and more from the maximum beam throughout the ship’s length is visible from the side of the bridge wing.

    A schematic diagram depicting the unified interpretations is also attached herewith.

    Navigation Bridge Visibility-d

    Figure 4

    For particular types of ships (Ships that are designed such that, in normal operations, they come along side, or operate in close proximity to, other vessels or offshore structures at sea.) such as tug/tow boat, offshore supply vessel (OSV), rescue ship, work ship (e.g. floating crane), in meeting the requirements of SOLAS regulation V/22.1.16, the bridge wings shall at least extend to a location from which the sea surface, at the lowest seagoing draught and at a transverse distance of 1,500 mm from the maximum beam throughout the ship’s length, is visible. If this ship type is changed to a type other than those addressed in this paragraph, then the interpretation in this paragraph would no longer apply.

    The use of a remote camera system may be accepted for ships of unconventional design, other than those mentioned in paragraph above, as means for achieving the view of the ship's side from the bridge wing, provided:

    1. the installed remote camera system is to be redundant from the circuit breaker to the camera and screen, including communication cables, i.e. the system is to provide on each side of the ship redundancy of:
      1. the power cables and circuit breakers from the main switchboard to the camera and the screen;
      2. the camera;
      3. the screen;
      4. the transmission lines from the camera to the display screen; and
      5. the components associated with these lines and cables;
    2. the remote camera system is powered from the ship's main source of electrical power and is not required to be powered by the emergency source of electrical power;
    3. the remote camera system is capable of continuous operation under environmental conditions as per UR E10;
    4. the view provided by the remote camera system complies with the requirements of regulation V/22.1.6 and is also displayed at locations where the maneuvering of the ship may take place;
    5. the upper edge of the ship’s side abeam is directly visible by the observer from locations where the maneuvering of the ship may take place.
  5. The height of the lower edge of the navigation bridge front windows above the bridge deck shall be kept as low as possible. In no case shall the lower edge present an obstruction to the forward view as described in this regulation;
  6. The upper edge of the navigation bridge front windows shall allow a forward view of the horizon, for a person with a height of eye of 1,800 mm above the bridge deck at the conning position, when the ship is pitching in heavy seas. The Administration, if satisfied that an 1,800 mm height of eye is unreasonable and impractical, may allow reduction of the height of eye but not less than 1,600 mm;
Navigation Bridge Visibility-e

Figure 5

  1. Windows shall meet the following requirements:
    1. To help avoid reflections, the bridge front windows shall be inclined from the vertical plane top out, at an angle of not less than 10 degrees and not more than 25 degrees;
    2. Framing between navigation bridge windows shall be kept to a minimum and not be installed immediately forward of any work station.
    3. Polarized and tinted windows shall not be fitted.
    4. A clear view through at least two of the navigation bridge front windows and, depending on the bridge configuration, an additional number of clear-view windows shall be provided at all times, regardless of weather conditions.

    Note: On ships of unconventional design which, in the opinion of the Administration, cannot comply with this regulation, arrangements shall be provided to achieve a level of visibility that is as near as practical to that described in this regulation.

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