84.14 Intensity of lights.§ 84.14 Intensity of lights.
(a) The minimum luminous intensity of lights shall be calculated by using the formula:I = 3.43 × 10 6 × T × D 2 × K−D Where: I is luminous intensity in candelas under service conditions, T is threshold factor 2 × 10−7lux, 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 (Table 84.14(b)):
|Range of visibility
(luminous range) of light
in nautical miles D
|Minimum luminous intensity of light in candelas for K = 0.8 I|