Regardless of your specific job, in the Navy you must also be a combat-ready sailor. The Navy has strict physical and medical requirements to make sure sailors are ready to fulfill their military duties. If you fail to meet these qualifications, you will no be allowed to join the Navy. In addition, some specific carer paths, such as aviation, diving and special warfare, have additional, more stringent requirements.

Age and Body Composition

To enlist in the Navy, you must be between the ages of 17 and 34 years old, while prospective officers must be between the ages of 19 and 35. In addition, you must meet the body composition requirements. The maximum allowed body fat percentage for men under the age of 40 is 22%. Men age 40 and older may have body fat percentage up to 23%. Women under the age of 40 must not exceed 33%, while women age 40 and up must not exceed 34% body fat.

Drug and Alcohol Use

The Navy administers two separate urinalysis tests during the enlistment and commissioning process to check for drug and alcohol use. Both tests must be negative to comply with the Navy's zero-tolerance drug and alcohol policy. A history of alcohol or drug abuse will also disqualify candidates.

Fitness

Sailors must also be able to pass the Navy Physical Readiness Test. This test includes sit-ups, push-ups and a timed 1.5 mile run. Sailors must complete as many sit-ups as possible within two minutes. This is repeated for the push-ups portion of the test. The specific requirements for each exercise vary based on age and gender.

Vision

For most Navy positions, sailors must have distance acuity vision of at least 20/40 vision in one eye and 20/70 in the other, or 20/30 vision in one eye and 20/100 in the other, or 20/20 vision in one eye and 20/400 in the other. Sailors may wear corrective lenses to achieve this standard. Some eye conditions that will disqualify you from service include chronic conjunctivitis, corneal dystrophy and retinal defects.

Ears, Sinuses and Mouth

The physical exam includes a complete hearing test. Sailors who use or have a history of using hearing aids are disqualified. Other sinus and dental conditions that prevent enlistment in the Navy include allergic rhinitis or chronic non-allergic rhinitis, chronic sinusitis and current use of orthodontic appliances other than retainers.

Other Conditions

The medical exam includes all body systems to detect any conditions that would prevent a sailor from fulfilling his duties or that put him at increased risk for injury or illness. Some conditions that may cause disqualification include a history of heart disease, psoriasis, any disease causing immunodeficiencies, HIV and diabetes mellitus.

Psychiatric Conditions

Several psychiatric and behavioral conditions will also prevent someone from joining the Navy. These include currently experiencing or having a history of schizophrenia or other psychotic disorders and mood disorders, including depression and bipolar. Some behavioral patterns and conditions that may disqualify a candidate include sleepwalking, eating disorders and a history of suicidal behavior.