5.2 Work Environment

  5.2.1 Climate

  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.

  5.2.3 Noise and Acoustics

Workplace noise should be maintained at levels that do not: (1) interfere with necessary voice, telephone and radio communications, (2) cause fatigue or injury and (3) degrade overall system effectiveness.

  5.2.4 Vibration

Uncomfortable levels of vibration should be avoided on the bridge. Vibrations on the bridge should be reduced to such extent that the bridge personnel are neither hindered in their functions nor put at a health risk.

  5.2.5 Illumination and Lighting

A satisfactory level of lighting should be available to enable the bridge personnel to complete such tasks as maintenance, chart and office work satisfactorily, both at sea and in port, daytime and night time.

  5.2.5.1 Dark Adaptation

Red or filtered white light should be used to maintain dark adaptation whenever possible in areas or on items of equipment requiring illumination in the operational mode. This should include devices in the bridge wings.

  5.2.5.2 Luminance Contrast

High contrast in luminance between work area and surrounding should be avoided, i.e. luminance of the task area should not be greater than 3 times the average luminance of the surrounding area.

  5.2.5.3 Flexible Lighting System

The lighting system should enable the bridge personnel to adjust the lighting in brightness and direction as required in different areas of the bridge and by the needs of individual devices. The following table lists the recommended general illumination:

  5.2.5.4 Light Dimming

A light dimming capability should be provided.

  5.2.5.5 Glare Avoidance

Upmost care should be taken to avoid glare and stray image reflections in the bridge environment.

  5.2.5.6 Lighting Sources

Lighting sources should be designed and located to avoid creating glare from working and display surfaces.

  5.2.5.7 Reflection in Windows

Reflection in windows of devices, instruments and consoles and other reflective enclosures should be avoided.

  5.2.5.8 Glare and Reflection Avoidance

Devices should be designed and fitted to minimize glare or reflection or being obscured by strong light.

  5.2.5.9 Flicker Avoidance

Light sources should not have a perceptible flicker.

  5.2.5.10 Lighting Controls

Lighting controls should be provided at entrances and exits of enclosed workplace areas.

  5.2.5.11 Lighting Control Illumination

Lighting controls should be illuminated.

  5.2.5.12 Interior Colour Design

For the interior nonsaturated colours should be chosen which give a calm overall impression and minimize reflectance. Bright colours should not be used. Dark or mid-green colours are recommended, alternatively blue or brown may be used.

  5.2.6 Occupational Safety

  5.2.6.1 Non-slip Surfaces

Wheelhouse, bridge wings and upper bridge decks should have non-slip surfaces.

  5.2.6.2 General Wheelhouse Safety

There should be no sharp edges or protuberances which could cause injury to personnel.

  5.2.6.3 Hand and Grab Rails

Sufficient hand- or grab-rails should be fitted to enable personnel to move or stand safely in bad weather. Protection of stairway openings should be given special consideration.

  5.2.6.4 Safety Equipment Marking

All safety equipment carried on the bridge should be clearly marked, be easily accessible and have its stowage position clearly indicated.