Circular Letter
MSC/Circ.982
GUIDELINES ON ERGONOMIC CRITERIA FOR BRIDGE EQUIPMENT AND LAYOUT
(adopted
on 5 December 2000)
1. The Maritime Safety Committee, at its
seventy-third session (27 November to 6 December 2000) adopted the annexed
Guidelines on Ergonomic Criteria for Bridge Equipment and Layout which have
been developed to assist designers in realising a successful ergonomic design
of the bridge, with the objective of improving the reliability and efficiency
of navigation.
2. These Guidelines have been prepared to
support provisions of regulation V/15 of the SOLAS Convention - Principles
relating to bridge design, design and arrangement of navigational systems and
equipment and bridge procedures.
3. Member Governments are invited to bring these
Guidelines to the attention of all parties concerned.
Annex.
GUIDELINES ON ERGONOMIC CRITERIA FOR BRIDGE EQUIPMENT AND LAYOUT
The
Guidelines are developed to realize a successful ergonomic design of the bridge
and the equipment on the bridge, which will improve the reliability and
efficiency of navigation. These Guidelines therefore contain ergonomic
requirements as well as a functionally oriented bridge layout to support the
mariner in his tasks by a user-centered design of the bridge equipment and
layout.
The
purpose of these Guidelines is to provide ergonomic requirements for the bridge
equipment and layout to render assistance to consistent, reliable and efficient
bridge operation.
These
Guidelines are intended to apply to new ships.
4. DESCRIPTION OF THE WORKSTATIONS ON THE
BRIDGE
Workstation
for navigating and maneuvering:
Main workstation for ship's
handling conceived for working in seated/standing position with optimum
visibility and integrated presentation of information and operating equipment
to control and consider ship's movement. It should be possible from this place
to operate the ship safely, in particular when a fast sequence of actions is
required.
Workstation
for monitoring:
Workstation from which
operating equipment and surrounding environment can be permanently observed in
seated/standing position; when several crew members are working on the bridge
it serves for relieving the navigator at the workstation for navigating and
maneuvering and/or for carrying out control and advisory functions by master
and/or pilot.
Workstation
for manual steering (Helmsman's workstation):
Workstation from which the
ship can be steered by a helmsman as far as legally or otherwise required or
deemed to be necessary, preferably conceived for working in seated position.
Workstation
for docking (bridge wing):
The workstation for docking
operations on the bridge wing should enable the navigator together with a pilot
(when present) to observe all relevant external and internal information and
control the maneuvering of the ship.
Workstation
for planning and documentation:
Workstation at which ship's
operations are planned (e.g. route planning, deck log). Fixing and documenting
all facts of ship's operation.
Workstation
for safety:
Workstation at which
monitoring displays and operating elements or systems serving safety are
co-located.
Workstation
for communication:
Workstation for operation
and control of equipment for distress and safety communications (GMDSS) and
general communications.
Fig.
1:
Example of function areas - showing a possible location of workstations
In
Appendix 2 the recommended equipment for the various workstations is listed.
5.1.1.1
Field of Vision
5.1.1.1.1
Minimum Field of Vision
The
view of the sea surface from the navigating and maneuvering Workstation should
not be obscured by more than two ship lengths or 500 m, whichever is less,
forward of the bow to 10° on either side under all conditions of draught, trim
and deck cargo.
5.1.1.1.2
Field of Vision around the Ship
There
should be a field of vision around the vessel of 360° obtained by an observer
moving within the confines of the wheelhouse.
5.1.1.1.3
Navigating and Manoeuvering Workstation
The
horizontal field of vision from the navigating and maneuvering workstation
should extend over an arc of not less than 225°, that is from right ahead to
not less than 22.5°, abaft the beam on either side of the ship.
5.1.1.1.4
Monitoring Workstation
From
the monitoring workstation, the field of vision should extend at least over an
arc from 90° on the port bow, through forward, to 22.5° abaft the beam on
starboard.
5.1.1.1.5
Bridge Wing
From
each bridge wing the horizontal field of vision should extend over an arc at
least 225° that is at least 45° on the opposite bow through right ahead and
then from right ahead to right astern through 180° on the same side of the
ship.
5.1.1.1.6
Main Steering Position
From
the main steering position (workstation for manual steering) the horizontal
field of vision should extend over an arc from right ahead to at least 60° on
each side of the ship.
5.1.1.1.7
Blind Sectors
The
safe look-out from the navigating and maneuvering workstation should not be
influenced by blind sectors.
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 navigating and maneuvering workstation, should exceed 10°. The
total arc of blind sectors should not exceed 20°. The clear sector between two
blind sectors should be at least 5°. Over an arc from right ahead to at least
10° on each side, each individual blind sector should not exceed 5°.
5.1.1.1.8
View of the Ship's Side
The
ship's side should be visible from the bridge wing. Bridge wings should be
provided out to the maximum beam of the ship. The view over the ship' side
should not be obstructed.
5.1.1.2
Windows
5.1.1.2.1
Lower Edge of the Front Window
The
height of the lower edge of the front windows should allow a forward view over
the bow for a person in a sitting position at the workstation for navigating
and manoeuvering and the workstation for monitoring.
Within
the required field of vision the height of the lower edge of the windows above
the bridge deck should be kept as low as possible. In no case should the lower
edge present an obstruction to the forward view as described in 5.1.1.1.
5.1.1.2.2
Upper Edge of the Front Window
The
upper edge of the front windows should allow a forward view of the horizon for
a person in a standing position with an eye height of 1.800 mm above the bridge
deck at the navigating and manoeuvering workstation, when the ship is pitching
in heavy seas. If 1.800 mm eye height is unreasonable and impractical, the eye
height may be reduced, but not less than 1.600 mm.
5.1.1.2.3
Framing Between Windows
Framing
between windows should be kept to a minimum and not be installed immediately
forward of any workstation, or the center-line. If stiffeners between windows
are to be covered, this should not cause further obstructions of the field of
view from any position inside the wheelhouse.
5.1.1.2.4
Front Window Inclination
To
help avoid reflections, the bridge front windows should be inclined from the
vertical plane top out, at an angle of not less than 10° and not more than 25°.
5.1.1.2.5
Rear and Side Window Inclination
To
help avoid reflections, rear and side windows should be inclined from the vertical
plane top out, at an angle of not less than 10° and not more than 25°.
Exceptions can be made for windows in bridge wing doors.
5.1.1.2.6
Removable Sunscreens
To
ensure a clear view and to avoid reflections in bright sunshine, sunscreens
with minimum color distortion should be provided at all windows. Such screens
should be readily removable and not permanently installed.
5.1.1.2.7
Glass Characteristics
Polarized
and tinted windows should not be fitted.
5.1.1.2.8
Clear View
A
clear view through at least two of the bridge front windows and, depending on
the bridge configuration, an additional number of windows with a clear view
should be provided at all times, regardless of the weather conditions.
5.1.2.1
Wheelhouse Dimensions
The
clear ceiling height in the wheelhouse should be designed with regard to the
installation of overhead panels and devices. The clear height between the
bridge deck surface covering and the underside of the deck head beams should be
at least 2.25 m. The lower edge of deckhead mounted equipment should be at
least 2.1 m above the deck in open areas, passageways and at standing
workstations.
5.1.2.2
View of the area in front of the bridge superstructure
It
should be possible to watch the area in front of the bridge superstructure from
the wheelhouse.
5.1.2.2.1
Position close to the Forward Center Window
A
position should be provided close to the forward center window.
If
the view in the center-line is obstructed by large masts, cranes, etc., two
additional positions giving a clear view ahead should be provided, one on the
port side and one on the starboard side of the center-line, no more than 5 m
apart.
5.1.2.2.2
Access to Front Window
A
second close approach access besides the position should be possible or the
width of the position should be sufficient to accommodate two persons.
5.1.2.3
Position of the Workstation for Navigating and Manoeuvering
The
workstation for navigating and maneuvering should be laid out if practicable,
at the starboard side close to the center-line.
5.1.2.4
Position of the Workstation for Manual Steering
The
workstation for manual steering should preferably be located on the ship's
center-line. If the view ahead is obstructed by large masts, cranes, etc., the
steering station should be located a distance to starboard of the center-line,
sufficient to obtain a clear view ahead. If the workstation for manual steering
is located off the center-line, special steering references for use by day and
night should be provided, e.g. sighting marks forward.
5.1.2.5
Position of the Workstation for Monitoring
The
workstation for monitoring should be laid out if practicable, at the port side
close to the center-line.
5.1.2.6
Bridge Wing Communication
An
internal communication system between the workstation for docking and the
workstation for navigating and manoeuvering should be provided when the
distance between the workstations is greater than 10m. An internal
communication system should always be provided between the workstation for navigating
and manoeuvering and open bridge wings. Where workstations are widely spread,
internal communication systems should be provided so that unhampered
communications can be achieved under all operating conditions. It is important
that all order/action communication systems be two-way.
5.1.2.7
Doors
All
wheelhouse doors should be operable with one hand. Bridge wing doors should not
be self-closing. Means should be provided to hold bridge wing doors open.
5.1.2.8
Portable Items
Portable
items, such as safety equipment, tools, lights, pencils, should be stored at
appropriate places, specially designed wherever necessary.
5.1.3
Accessibility and Movement
5.1.3.1
Clear Route
A
clear route across the wheelhouse from bridge wing to bridge wing should be
provided. The width of the passageway should be at least 1200 mm.
5.1.3.2
Adjacent Workstation Distances
The
distance between adjacent workstations should be sufficient to allow
unobstructed passage to persons not working at the stations.
The
free passage in passageways between different workstation areas should be at
least 700 mm. The workstation operating area should be part of the workstation
not of the passageway.
5.1.3.3
Passageway Dimensions
The
distance from the bridge front bulkhead, or from any consoles or installations
placed against the front bulkhead, to any consoles or installations placed away
from the bridge front should be sufficient for two persons to pass each other.
The distance of a passageway between the front bulkhead and any consoles should
preferably be at least 1000 mm, and not less than 800 mm.
5.2.1.1
Effective Temperature
The
optimum range of effective temperature for accomplishing light work while
dressed appropriately for the season or climate is 21 - 27°C in a warm climate
or during the summer, and 18 - 24°C in a colder climate or during the winter.
5.2.1.2
Temperature Differences
Temperature
difference between any two points within the workplace should be maintained
below 5°C, e.g. the temperature of the air at floor level and at head level.
5.2.1.3
Humidity
Humidity
should be maintained between 20% and 60% with 40% to 45% preferred.
Approximately 45% relative humidity should be provided at 21°C. This value
should decrease with rising temperatures, but should remain above 20% to
prevent irritation and drying of body tissues, eyes, skin, and respiratory
tract.
5.2.2
Ventilation and Air-conditioning
5.2.2.1
Air-conditioning
The
wheelhouse should be equipped with an adequate air-conditioning or mechanical
ventilation system to regulate temperature and humidity. The temperature and
the humidity should be adjustable within the limits of the foregoing
requirements 5.2.1, by closed wheelhouse doors and windows.
5.2.2.2
Hot Air Discharge
Heating
systems should be designed so that hot air discharge is not directed at
personnel.
5.2.2.3
Cold Air Discharge
Air
conditioning systems should be designed such that cold air discharge is not
directed at personnel.
5.2.2.4
Air Velocities
Ventilating
systems should not produce air velocities exceeding 0,5 m/s. If possible, the
preferred air velocity of 0,3 m/s should be used to preclude manual pages from
being turned or papers from being blown off work surfaces.
Workplace
noise should be maintained at levels that do not:
1) interfere with necessary
voice, telephone and radio communications,