Why is it green for starboard?

 

Starboard and Port Marks

Here’s how starboard became green

1834
Ships of the City of Dublin Steamship Company were equipped with white masthead, green starboard lights and red port navigation lights.
1836
The P&O Company of Southampton had a different arrangement; green for port, green and red for starboard.
1847
The British Admiralty ordained that starboard was to be green and port red.
1853
The Prussian Ministry of Trade prescribed the British lighting rules for its steamers.
1858
France, Austria, Hungary and the North German seaboard countries also signed up.
1889
27 other seafaring nations followed suit and adopted international maritime regulations ( known today as the International Collision Regulations ColRegs )

This colour code also applies to lighthouses. Lighthouses on the  starboard side of harbours (when coming in from sea) are always green. Except for the Americas, Japan, South Korea and the Philippines which are opposite.

Written by NATIONAL MARITIME COLLEGE

The National Maritime College (NMC) is a Registered Training Organisation providing competency-based boat training and education. The College offers boat licence and jet ski (PWC) licence courses and tests designed to improve boating skills and awareness. You can expect friendly and professional training from from us. It is the "personal touch" and dedication to improving safety on the water whilst instilling - confidence, knowledge and good boat handling skills that sets us apart.