Page 474 - Handbook of Electrical Engineering

MISCELLANEOUS SUBJECTS 463

Table 18.1. (continued)

Location and equipment Illumination level
in lux, see Note 1
Material storage and handling yards 50
Road tanker loading areas 25
Drill pipe laydown area 10
General car parking area 1 to 5
Note 1: Some oil companies specify the level of illumination to be
floor level, whilst others prefer it at a working desk height,
e.g. 0.7 to 0.85 m.
Note 2: The lighting level in the central control room can be arran-
ged to be wholly or partly adjustable so as to minimise glare
and eyestrain whilst operating visual display units (VDU)
or man–machine interfaces (MMI).

Helideck lighting is a specialised subject that is covered by national and international regulations.

It is recommended to supply the helideck landing circle light fittings from a DC service e.g.
110 VDC uninterruptible supply, that should have a 110 VAC back-up supply so that the DC system
can be maintained without switching off the circle lighting.
A comprehensive source of general information on lighting is Reference 1. It also describes
in detail how to calculate lighting levels.

18.2 NAVIGATION AIDS
This sub-section mainly applies to offshore and marine installations, and is given as general guid-
ance. For more detail appropriate references should be sought and carefully studied, and their latest
revisions verified.

Navigation aids consist of the following equipment:
• Flashing marker lights.
• Fog horns.
• Platform nameplates.
• Aircraft hazard lights.
• Helideck landing facilities.
• Radio communications and beacons.
• Radar.
• Echo-sounding and sonar.

18.2.1 Flashing Marker Lights

A typical requirement is that recommended by the British Department of Trade document ‘Standard
Making Schedule for Offshore Installations’,