Appendix 1 - Definitions
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC/Circular.982 – Guidelines on Ergonomic Criteria for Bridge Equipment and Layout – (Adopted on 20 December 2000) - Annex - Guidelines on Ergonomic Criteria for Bridge Equipment and Layout - Appendix 1 - Definitions

Appendix 1 - Definitions

  Alarm: An alarm announces by audible means, or audible and visual means, a condition of an abnormal situation requiring attention.

  Alphanumerics: Characters presented on a visual display as letters, numbers, digits, and usually other characters, such as punctuation marks or combinations of them.

  Ambient Light: Light originating from sources other than the operator's visual displays, i.e., the general level of illumination on the bridge due to sunlight or lights and lamps.

  Ambient Noise: All of the background sounds in the work environment, e.g., the general level of background noise on the shipbridge.

  Brightness: An attribute of visual sensation that is determined by the intensity of light radiation reaching the eye. Along with hue and saturation, a component of perceived colour.

  Character: A letter, digit, or other symbol that is used as part of the organization, control, or representation of data. A character is often in the form of a spatial arrangement of adjacent or connected strokes.

  Character Size: Measured by the height of a displayed character in terms of its visual angle.

  Coding: Use of a system of symbols, shapes, colours, or other variable sensory stimuli to represent specific information.

  Console: The structural framework for the integration of devices, equipment, and storage and which together compromise a workstation.

  Contrast: The difference in luminance between foreground objects and their background or, generally, between any two areas of a display, measured with the contrast ratio (division of the luminance of the foreground by the luminance of the background).

  Control: A mechanism used to regulate or guide the operation of a machine, equipment component, subsystem, or system.

  Cursor: A highlighted, moveable indicator on the computer screen that shows the current location for data entry, editing, or selection of a displayed object.

  Display (Visual): Means which presents visual information, including conventional instrumentation.

  Display Field: An area of the display screen reserved for the display of information.

  Effective Temperature: An index which combines into a single value the effect of temperature, humidity, and air movement on the sensation of warmth or cold felt by the human body. The numerical value is that of the temperature of still, saturated air which would induce an identical sensation.

  Ergonomics: The study and design of working environments (e.g., workstation, cockpit, ship bridges) and their components, work practices, and work procedures for the benefit of the worker's productivity, health, comfort, and safety. Application of the human factor in the analysis and design of equipment, work and working environment.

  Field of Vision: Angular size of a scene that can be observed from a position on the ship's bridge.

  Glare: Excessive demand for visual adaptation brought on by the retina's exposure to more light than it can tolerate. Produced when any luminance within the visual field is sufficiently greater than the luminance to which the eye is adjusted.

  Highlighting: Emphasizing displayed data or format features, e.g., through the use of underlining, bolding, or inverse video, for calling the user's attention to some displayed area or information.

  Hue: One component of the perception of colour (for example, red, green, yellow). Other components are saturation and brightness.

  Icon: Pictorial or other nonverbal representation of objects or actions.

  Illumination: The amount of light (luminance flux) falling on a surface, measured in lumen/m2 = lux.

  Input Device: A workstation component used for data entry and display control, e.g., keyboard, trackball, mouse. .

  Label: Alphanumeric information that identifies or describes an object or displayed data.

  Layout: The physical arrangement of the parts and components that make up a module or a unit of equipment.

  Line of Sight: An imaginary line extended from the plane of the viewer's eyes; the horizontal line of sight occupies the same horizontal plane as the centre of the pupils. The normal line of sight declines 15 degrees below the horizontal; maintaining a horizontal or higher line of sight takes effort and can be fatiguing over time.

  Luminance: Luminance is the amount per unit area emitted or reflected from a surface and is measured in candela per square metres (cd/m2).

  Menu: A set of related options listed together for selection by the user, i.e. a type of dialogue in which a user selects one item out of a list of displayed alternatives.

  Mode: An internally defined state or condition of computer operation, such as keyboard input mode, help mode, edit mode, save mode, planning mode or operational mode.

  Reflection: A mirror image of the surrounding environment that is coincidentally superimposed on screen content.

  Resolution: A characteristic of a visual display, expressed in pixels per square inch.

  Symbol: A graphic or alphanumeric representation of something by reason of relationship, association, or convention.

  Workstation: The combination of all job-related items, including the console with all devices, equipment and the furniture, to fulfil certain tasks.


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