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the ability of controllers to observe crucial areas of operations such as the runways, taxiways, approaches and circuits.

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the ability to observe the smallest size of aircraft commonly using the aerodrome.

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the ability to observe unusual circumstances or emergencies e.g. wheel fires.

3.5  The use of electronic aids such as SMR or Closed Circuit Television (CCTV) to enhance the view from the VCR will only be considered for approval in exceptional circumstances.
3.6  Reflections in the Visual Control Room glass and sun or lamp glare through the windows are to be kept to a minimum (25).
3.7  Positioning of Visual Display Units should take into account any reflection or glare which is likely to affect the operation of the equipment (26). This is particularly important in the Visual Control Room.
3.8  Glare-proof shades or blinds which can be raised or lowered may be required for windows.
3.9  Visual Control Room operating positions must permit optimum visibility of ground and air operations’ azimuth and elevation (27) whilst allowing the controller to refer easily to all the information on display (28).
3.10  Siting of working positions within the Visual Control Room will primarily be determined by the location of the tower in relation to the manoeuvring area, the most frequently used runway and the approach direction. Secondary considerations are simultaneously occupied operating positions and their functions (control of arriving and departing traffic against ground movements, the clearance delivery position, operation of the lighting panel, etc).
3.11  A pair of binoculars is required (29). Additional pairs may be required for other operational positions in the Visual Control Room.

4  Furniture
4.1  Control room layout should be such that controllers at operational positions are able to operate without distracting one another (30). Staff should be able to use a normal speaking voice when talking to one another, using RTF or telephones irrespective of aircraft or other noise (31).
4.2  Desks and equipment should provide satisfactory working conditions for each controller and assistant and facilitate liaison between them (32).
4.3  Facilities to accommodate manuals and documents, and display information such as NOTAM, weather and royal flights are to be provided (33). Information of a more permanent nature such as instrument approach procedures, topographical maps, telephone and emergency check-lists is to be conveniently located about the position (34).

5  Noise
Ambient noise levels within operations rooms should equate to the 'quiet office' environment (35) (approximately 50 dB(A) – source 'Noise Abatement' by C.Duerden,1972; Butterworth).

6  Lighting
6.1  Suitable minimum or non-glare lighting shall be provided to allow the controller to read and record information (36).
6.2  Lighting in the Visual Control Room must be arranged so that it does not diminish the ability of the controller to survey the aerodrome and its vicinity at night (37).
6.3  Operational lighting should be variable in intensity and direction for maximum flexibility (38).
6.4  Ambient lighting in operations rooms and Visual Control Rooms should be kept to a level consistent with good working conditions and with reflections reduced as much as possible (39). Door openings to lighted adjacent spaces should be screened so that light will not interfere with a controller’s vision when doors are opened (40).
6.5  Emergency lighting shall be provided in operational areas in order that controllers will have sufficient light to be able to continue a service in the event of a mains power failure (41).

7  Heating and Air Conditioning
7.1  Air circulation must be sufficiently adequate to ensure that windows in Visual Control Rooms can be and will remain demisted (43); it shall also allow satisfactory ambient working conditions in operations rooms (44).
　
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本文鏈接地址：CAP 670 Air Traffic Services Safety Requirements 1(58)