Table 2.

Colour vision requirements for obtaining a driving license in selected states of the USA.

Country	Colour vision requirements	Further recommendations
Alabama26	New and commercial drivers Using Keystone view colour vision test to distinguish red, amber and green	Nil
Arizona27	Commercial drivers only Using Keystone view colour vision test	Nil
Maryland28	Commercial drivers only Using Stereo Optical Optec 1000 colour vision test	Nil
Indiana29	Commercial drivers only Test not specified	Nil
Montana30	Commercial drivers only Using Stereo Optical Optec 1000 colour vision test	Nil
Nebraska31	Commercial drivers only Test not specified	Nil
Ohio32	Required but not specified	Nil
Tennessee33	Commercial drivers only Using Stereo Optical colour vision test	Nil
Texas34	New drivers Test not specified	Nil
Massachusetts35	All drivers Using Stereo Optical Optec 1000 colour vision test to distinguish red, amber and green	Nil
Washington36	New and commercial drivers Test not specified	Nil
Wisconsin37	Commercial drivers only Using Stereo Optical colour vision test	Nil