8. pants

Intensity of

lights

(a) The minimum luminous intensity

of lights shall be calculated by using the formula:

I = 3.43 x 106 x T x D2 x

K-D

where I is luminous intensity in candelas under service

conditions,

T is threshold factor 2 x 10-7 lux,

D is range of visibility (luminous range) of the light in

nautical miles,

K is atmospheric transmissivity.

For prescribed lights the value of K shall be 0.8, corresponding

to a meteorological visibility of approximately 13 nautical

miles.

(b) A selection of figures derived

from the formula is given in the following table:

Range of visibility (luminous

range) of light in nautical miles

D

Luminous intensity of light

in candelas for K=0.8

I

1

2

3

4

5

6

0,9

4,3

12

27

52

94

NOTE: The maximum luminous

intensity of navigation lights should be limited to avoid undue

glare. This shall not be achieved by a variable control of the

luminous intensity.