Color vision test for electricians

Updated November 2026

Electrical work relies on color. Insulation colors tell you which conductor is the neutral and which is the equipment ground, and many installations use colors to show phase and system. That is why some electrical apprenticeships and employers check color vision before or at the start of training.

This page is general information, not medical or legal advice.

Why color matters in electrical work

The National Electrical Code (NFPA 70) uses color to identify conductors:

Grounded (neutral) conductors: white or gray insulation, or three continuous white stripes on insulation that is not green (NEC 200.6, for 6 AWG and smaller).
Equipment grounding conductors: bare, or green, or green with one or more yellow stripes (NEC 250.119).
Ungrounded (hot) conductors: where a building has more than one voltage system, each one must be identified by phase and system, and the identification method must be documented or posted at each branch-circuit panelboard (NEC 210.5(C)).

Color schemes such as black, red and blue for 120/208 V, or brown, orange and yellow for 277/480 V, are common industry practice, not colors the NEC requires. Color codes are also common in control wiring, data cabling and on components.

Do electrical apprenticeships test color vision?

There is no single national rule. It depends on the program and the employer. Two examples:

IBEW Local 340 says about its Inside Wireman apprenticeship: "Wiring is frequently color coded for connection purposes; therefore, the worker cannot be colorblind."
The Texas Gulf Coast Electrical JATC says accepted applicants "may be required to take a physical exam which will include color blindness."

Check the requirements of the program you are applying to before the application deadline.

Can you work as an electrician with a color vision deficiency?

It depends on the type and degree of the deficiency, on the program and on the work. Some programs do not accept applicants who are colorblind, others check color vision as part of a physical exam. If you are unsure, take a screening first, then see an eye care professional, who can tell you the type and degree. Bring that result when you talk to the program.

For contractors, JATCs and staffing agencies

If you screen apprentices or new hires, use the same method for everyone in the same job category and keep results confidential and separate from personnel files. In the U.S., EEOC guidance treats vision tests as medical examinations, which may only be done after a conditional job offer.

Frequently asked questions

Can you be an electrician if you are colorblind?

It depends on the program, the employer and the type and degree of the deficiency. Some programs state that applicants cannot be colorblind, others include color vision in a physical exam.

Which colors does an electrician need to recognize?

At minimum the conductor identification colors: white or gray, green or green with yellow stripes, and the phase colors used where you work, often black, red, blue, brown, orange and yellow.

Which test is used?

The program or its examining doctor decides. Plate tests based on the Ishihara principle are the most common screening for red-green deficiency.

Will an apprenticeship accept the online test on this site?

It is not an official exam. Use it as a private pre-check and follow your program's instructions.