THE SCHEDULE INTERNATIONAL REGULATIONS FOR PREVENTING COLLISIONS AT SEA, 1972
(as amended by Resolution A464(XII) and Resolution A626(15))

ANNEX I Positioning and technical details of lights and shapes

7 Colour specification of lights
The chromaticity of all navigation lights shall conform to the following standards, which lie within the boundaries of the area of the diagram specified for each colour by the International Commission on Illumination (CIE).
The boundaries of the area for each colour are given by indicating the corner co-ordinates, which are as follows:
(i) White
x	0.525	0.525	0.452	0.310	0.310	0.443
y	0.382	0.440	0.440	0.348	0.283	0.382
(ii) Green
x	0.028	0.009	0.300	0.203
y	0.385	0.723	0.511	0.356
(iii) Red
x	0.680	0.660	0.735	0.721
y	0.320	0.320	0.265	0.259
(iv) Yellow
x	0.612	0.618	0.575	0.575
y	0.382	0.382	0.425	0.406