BASIC RULES

• The number of light levels recommended depends on the height of the structure;

• The number and arrangement of light units at each level should be placed so the lighting is visible from every angle in azimuth;

• Lights are applied to display the general definition of an object or a group of buildings;

• The top obstruction lights should be placed sufficiently below the top so as to minimize contamination by smoke, etc

• The diameter of the structure determine the number of obstruction lights installed at the top and at each light level.

LIGHTS SPECIFICATIONS

• Low intensity lights should be used for structure with H ≤ 45 m during night time, if those are considered inadequate, than medium – high intensity lights should be used.

• Medium intensity lights type A,B or C should be used to lit extensive object (group of buildings or tree) or structure with 45 m < H ≤ 150 m.

• Note: Medium intensity lights, type A and C should be used alone, whereas medium intensity lights, Type B should be used either alone or in combination with LIOL-B.

• High intensity type A, should be used to indicate the presence of an object if its H > 150 m and an aeronautical study indicates such lights to be essential for the recognition of the object by day.

AVIATION OBSTRUCTION LIGHT MARKINGS

There is 3 option for lighting a chimney with aviation obstruction light systems.

1. If the chimney is to be lighted only at night with red light

• If the authorities state that there is no need to light the day

• If the chimney marked with paint (white-red strip)

2. If the chimney is to be lighted day and night with white light

3. If the chimney is to be lighted with white light at daytime and with red light at night time

• If the authorities state that white light is too much discomfortable at night