Maritime health screening
Take a free color vision screening designed for seafarers and maritime professionals. Check how well you can distinguish colors used in navigation lights, signal flags, and charts.
Key facts for seafarers before you take the online screening test.
Color blindness (color vision deficiency) means difficulty distinguishing certain colors—most often red and green. It is usually inherited and ranges from mild to strong. Many people do not realize they have it until a screening or medical check.
Safe watchkeeping depends on correctly reading navigation lights, buoy colors, signal flags, alarm indicators, and chart symbology. Misreading a color can delay a critical decision at sea.
STCW medical fitness and company standards often include color vision checks. This online screening helps you prepare for exams and spot issues early—before they affect certification or employment.
You will view 12 plates. Each plate has a 15-second timer. Choose the number you see—or select “I see nothing” if no figure is clear.
This is not a medical diagnosis. Abnormal or uncertain results should be followed up with a professional eye examination before making career or certification decisions.
Overall Score
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These results are generated by an online screening tool and are not a clinical diagnosis. Do not use them alone for medical fitness, certification, or employment decisions. Consult a qualified eye care professional for a definitive assessment.
How color blindness affects maritime work, and what to expect from this screening.
The most common form is red–green deficiency (protan and deutan types). Blue–yellow deficiency (tritan) is less common. Complete color blindness (monochromacy) is rare. This screening focuses mainly on patterns associated with red–green deficiency using colored-dot plates.
From port-side and starboard lights to buoyage systems and bridge alarms, maritime operations rely on reliable color recognition. Flag administrations and employers may require documented color vision fitness for certain ranks. Early screening helps you plan training, medical checks, and career pathways with fewer surprises.
Common questions about online color vision screening for maritime careers.
This online screening can indicate whether you may have a color vision deficiency, but accuracy depends on screen calibration, lighting, and how carefully you take the test. It is a helpful first step, not a substitute for a clinical eye examination.
No. Seafarers.in provides this tool for educational screening only. A licensed eye care professional must confirm any color vision deficiency using standardized clinical methods.
Color vision standards vary by flag state, shipping company, and role (especially bridge and lookout duties). Some positions require normal color vision for signal lights and navigational aids. Always check the medical fitness standards that apply to your certificate and employer.
The test shows plates made of colored dots that form numbers. People with normal color vision usually see one figure; people with certain color deficiencies may see a different figure or none at all. It is commonly used to screen for red–green color vision problems.
Yes—if your screening result is inconclusive, suggests a deficiency, or you struggle with maritime signal colors, navigation lights, or charts. An optometrist or ophthalmologist can perform a full color vision assessment.
Most people finish the 12-plate screening in a few minutes. Each plate has a 15-second timer to keep answers consistent and reduce second-guessing.
