Colour vision test

 Color vision tests check the ability to distinguish colors, are used to screen applicants for jobs in fields where color perception is essential, such as pilots,

divers, in the military, or electronics. Colour blindness is most commonly a genetic condition. The most common hereditary Colour vision defect is failure of red-green discrimination (prevalence is 8% in males and 0.5% in females).

Very few people who are colorblind are blind to all colors. The usual colors that people have difficulty with are greens, yellows, oranges and reds.

 The most common tests used are Ishihara plate test and City University.

Subjects who pass the City University test but fail the Ishihara plate test are likely to have practical difficulties with only the most demanding color discrimination tasks in an occupational context, such as situations involving color recognition of transport signals. In these cases lantern and trade tests can be used to determine suitability (HSE 2005).

International standards

  1. Offshore medical: Colour vision shall be assessed at the initial examination. Colour vision deficiency and color blindness shall not result in forfeiture of a medical certificate, but the individual must be informed of the finding. (Norwegian Directorate of Health 2012)
  2. Special requirements may exist for certain functions (maritime positions, certain types of skilled workers), but shall not influence issuance of a general medical certificate.
  3. Offshore medical: Colour vision is only required for specialist tasks such as electrical work and need not be requested unless specifically required for colour dependent tasks.

 (UK Offshore Oil and Gas 2008)

  1. Offshore medical: A full vision test including color discrimination and depth perception is required. Color perception should be adequate for the particular type of employment to be undertaken. (GoM BP 2012)


d-      Firefighters; Persons with severe color vision loss will likely fail the acuity requirement. Formerly, color vision deficiency was listed as a Category B medical condition. However, it is felt that within most cases this condition will not affect the ability of a member to safely perform the essential functions of his or her job. The fire service physician should consider the color vision deficiency of the individual and consider the color vision requirements of the member’s job and reach an individual determination. (NFPA 2012).

  1. Firefighters; color vision test is part of the minimum requirments(AFAC 2006).

f-       Divers, The initial examination should include colour vision test.

(HSE UK, MA1, 2011)

g-      Divers, color vision must be adequate for the type of diving activity divers.

(The Norwegian Board of Health 2000)

h-      OSHA Standard: Hazardous Waste Operations and Emergency Responses (HAZWOPER): color vision test is required for HAZMAT team members and emergency response team (OSHA, 2009).

  1. Drivers; color vision test should be performed, however; Need not notify DVLA. Driving may continue with no restrictions on the license.

(UK DVLA 2014).

  1. Drivers: There is not a colour vision standard for drivers, either private or commercial. Doctors and optometrists should, however, advise drivers who have a significant colour vision deficiency about how this may affect their responsiveness to signal lights (Austroads 2012).
  3. Commercial drivers; they need to have the ability to recognize the colors of traffic signals and devices showing standard red, green and amber;The term "ability to recognize the colors of" is interpreted to mean if a person can recognize and distinguish among traffic control signals and devices showing standard red, green and amber, he or she meets the minimum standard, even though he or she may have some type of color perception deficiency. If certain color perception tests are administered, (such as Ishihara, Pseudoisochromatic, Yarn) and doubtful findings are discovered, a controlled test using signal red, green and amber may be employed to determine the driver's ability to recognize these colors( US. Physical Qualifications for Drivers 2015).


The test is recommended for fire fighters, divers, offshore, electricians and other safety critical positions.


  1. HSE, UK, Colour vision examination A guide for employers,2005.
  2. From:
  3. Guidelines - health requirements for persons working on installations offshore. Norwegian Directorate of Health 2012.
  4. Medical Aspects of Fitness for Work Offshore ( 2008 The United Kingdom Offshore Oil and Gas)
  5. GoM Medical Aspects of Fitness for Offshore Work Safety Work Practice (BP 2012)
  6. NFPA 1582, Chapter 6 Medical Evaluations of Candidates - 2012
  7. Australasian Fire Authorities Council (AFAC) Medical Guidelines for Firefighters, 2006
  8. HSE UK, The medical examination and assessment of divers (MA1) 2011,
  9. The Norwegian Board of Health, 2000, Norwegian guidelines for medical examination of occupational divers. From:
  10. Doctors’ Guide to Medical Examinations for Workers engaged in Hazardous Occupations in Industrial Undertakings - Occupational Safety and Health – 2004, Hong Kong.
  11. OSHA, Screening and Surveillance: A Guide to OSHA Standards, 2009
  12. At a glance Guide to the current Medical Standards of Fitness to Drive'. Drivers Medical Group, DVLA, UK, May 2014
  13. Austroads (2012) ASSESSING FITNESS TO DRIVE, for commercial and private vehicle drivers, ISBN: 978-1-921991-86-8
  14. U.S. Code of Federal Regulations. 391.41 Physical Qualifications for Drivers,From:
  15. Medical Examination Report, For Commercial Driver Fitness Determination 2015.



Parent Category: Fitness for Work