For any of your patients interested in military service, but are color deficient or not correctable to 20/20, I have posted a "simplified" Navy, Coast Guard, Marine to go-by list as the featured image on this blog. The other services are similar. You will notice there is a limited number of jobs.
“Jobs that do not require normal color perception”
“Jobs and ratings that must correct to 20/20”
Note: Color vision standards recently changed for aviation/pilots – see attached waiver guide. They must score 12/14 on a PIP Test. If they fail the PIP Test, they are given a computerized color vision test. The Navy, Coast Guard, Marines, Army now accept color vision deficient applicants who score “mild” on the Waggoner CCVT, Rabin CCT, or the Barbur CAD. The Air Force only accepts applicants who score “mild” on the Rabin CCT. These are the “only” three computerized color vision tests accepted by any of the U.S. Military Services.
12.2 Color Vision Abnormalities
Last Revised: AUG 16 (Last Reviewed: AUG 16)
AEROMEDICAL CONCERNS: Color vision is required to accurately identify warning lights and color visual displays in the cockpit, airfield and shipboard lighting, colored smoke in combat, ground target identification, and aircraft formation lights. Interactions with other optical devices, such as laser eye protection glasses and protective visors may worsen color vision problems. For testing purposes, proper instructions and lighting are critical to accurate results. Best corrected spectacles are recommended, but no tinted or colored lenses may be worn during testing, as that will decrease the sensitivity of the test for detecting color vision deficiency.
WAIVER: Applicants: the condition is CD and waivers are typically not considered for applicants that cannot pass the required color vision tests. Certain non-aircrew positions require adequate color vision, including ATC, UAV, and sonar display operators (anti-sub aircraft). Waivers have been granted for Aeromedical and other Class II aircrew applicants on a case-by-case basis.
Designated: Waivers for designated personnel with a change in color vision may be considered on a case-by-case basis.
COLOR TESTS:
- Pseudo-Isochromatic Plates (PIP) are considered a primary test of color vision. Approved: Ishihara 38-plate edition, Pseudoisochromatic Ishihara Compatible (PIPIC) 24-plate edition (Waggoner PIP24)
- Scoring: 12 (or more) of 14 correctly identified red/green numerical test plates constitutes a passing score. Passing criteria is 12 or more plates correctly read, i.e., no more than 2 errors.
- Use one demonstration and 14 test plates (the orange number on page one is a demo plate only, and not a test plate, and should not be counted). Directions: Best corrected vision, Daylight Illuminator stand or a light source ~ 6500 degree Kelvin temperature “Daylight” fluorescent bulb, three seconds each page, no tracing allowed, random order. Regular white incandescent bulbs may not be used as they reduce the sensitivity of the test.
- Other editions of pseudoisochromatic plates may not have the correct types of plates (numbers only required). Research has shown that individuals scoring 11 (or less out of 14) on the PIP test do not have normal color vision.
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Farnsworth Lantern (FALANT), The Farnsworth Lantern was designed in the 1940’s to pass mildly color vision deficient individuals for Naval submarine service. Passing the FALANT does not ensure normal color vision. Original model or Optec 900 accepted.
- Passing criteria for FALANT remains 9 of 9, or 16 of 18 correct responses. Directions: normal room lighting, best corrected vision worn, both eyes open, 8 foot test distance, random presentation of targets, two seconds each target. Prior to testing, read the instructions to the patient exactly as written on the side of the unit to ensure predictable responses, and follow all directions on the guide.
- As of 01 January 2017, the FALANT will no longer be acceptable for applicants for any class, but those designated and student aviators who have passed the FALANT prior to phase-out will be grandfathered for their career, unless a documented color vision degradation is identified, which requires further evaluation to exclude progressive or acquired disease.
- Computerized Color Vision Tests (CCVT) may be either used as a primary test of color vision, or may be used as a backup test for PIP or FALANT failures.
Computerized Tests (validated and approved):
- Waggoner CCVT: A score of “normal” or “mild” color vision deficiency in red, green or blue is acceptable for aviation. Tested binocularly (both eyes open). May test monocularly for isolating and tracking acquired color vision defects. Both desktop and tablet versions are acceptable.
- Colour Assessment & Diagnosis (CAD, City University London): A score of less than or equal to 6 CAD units for all three cone types in each eye is acceptable. This test is given binocularly (both eyes at the same time).
- Cone Contrast Test (CCT, Rabin): A score of 55 or greater in each eye is required for all three cone types. This test is given monocularly (one eye at a time).
- Computer tests shall be administered per manufacturer recommendations with regard to distance, lighting, screen calibration, and monocular or binocular testing. Best correction worn. Computerized tests must be utilized per manufacturer’s instructions; such as administration processes and calibration, room lighting, and screen brightness. Computer-printout grade sheets should be submitted with the physical exam, to ensure objectivity and correctness.
INFORMATION REQUIRED: If a designated aviator fails the PIP, and either a FALANT or computerized test (worse than mild defect), an ophthalmologic evaluation is required to screen for acquired pathology. Additionally, a practical test of color vision must be performed to demonstrate operational ability and be administered with the objective oversight of the flight surgeon, type standardization instructor, and type NATOPS officer as observers. Tests would include identification of cockpit lighting, gauges, safety indicators, cockpit display symbology, map symbology for both cockpit and actual charts (hazards/obstacles, airspace coordination areas, route markings, etc.), identification of shipboard and landing field lighting, and ALDIS lights. For Marines, smoke color identification testing is also required. A control group of two additional aviators with normal color vision is recommended for comparison. Commanding Officer endorsement is required.
TREATMENT: N/A.
DISCUSSION: Defective color vision is overwhelmingly congenital, and mainly involves red and green cones, due to X-linked genetics. Blue cones are encoded on Chromosome 7. In Caucasians, approximately 8% of males have inherited red/green color defective vision. Of males, 2% of the population have only two cones, “dichromats,” and are severely deficient.
The majority of color deficient individuals have three cone types, “trichromats”, but are red or green weak. Moderate to severe color deficient individuals have increased difficulty interpreting VASI and PAPI lights correctly, as well as difficulty with navigation and shipboard lighting and colored smoke identification. Moderate and severe color deficient individuals also take a longer time to interpret color signals and targets, while also making more errors.
Blue color deficiency may be acquired by ocular diseases, including cataracts, optic neuritis, macular degeneration, central serous retinopathy, or side effects of medications or toxins.
Mild color vision deficiencies are considered acceptable for safe and effective flight. Moderate-to-severe red-green abnormalities are the most problematic for aviation, and those individuals can, unfortunately, sometimes pass the FALANT. Any degree of color vision deficiency, even mild, may be considered as a potential causal or contributing factor in mishap investigations.