Just added the Third class cert as reference to a commercial tag. Without going into more detail
IT DONT LOOK THAT MUCH DIFFERENT THAN A CLASS A
we all know that a whack job person isn't going to run and tell on himself
Third class certifications require the least involved examinations of all medical certifications. They are required for those intending to be pilot-in-command of an aircraft under the Private or Recreational pilot certificates or while exercising solo privileges as a student pilot. To qualify for a third class medical certificate, pilots must meet the following requirements:
Distant vision: 20/40 or better in each eye separately,[22] with or without correction
Near vision: 20/40 or better in each eye separately, with or without correction, as measured at a distance of 16 inches (410 mm)
Color vision: Demonstrate the ability to perceive the colors necessary for the safe performance of airman duties
Hearing: Demonstrate the ability to hear an average conversational voice in a quiet room, using both ears, at a distance of six feet, with their back turned to the examiner, or pass an approved audiometric test
Ear, Nose, and Throat: Exhibit no ear disease or condition manifested by, or that may reasonably be expected to be manifested by, vertigo or a disturbance of speech or equilibrium
Blood Pressure: Under 155/95
Mental Status: No diagnosis of psychosis, bipolar disorder, or severe personality disorders
Substance Dependence: No dependence on alcohol or any pharmacological substance in the previous two years
For pilots under 40 years of age, third class medical certificates expire on the last day of the month they were issued, five years from the date of issue. The FAA changed this rule from three to five years on July 24, 2008.[23][24] For all others, they expire on the last day of the month they were issued, two years from the date of issue.
Second class[edit]
A second class medical is required for those intending to exercise the privileges of the commercial pilot certificate. It is possible to obtain a commercial pilot certificate while holding a third class medical, but the licensee cannot exercise privileges beyond that of a private pilot.
To qualify for a second class medical certificate, pilots must meet the requirements for the third class certificate plus:
Distant vision: 20/20 or better in each eye separately, with or without correction
Intermediate vision: 20/40 or better in each eye separately, with or without correction, at age 50 and over, as measured at 32 inches
Second class certificates are valid until the last day of the month, twelve months after they were issued. The certificate holder may then only exercise the privileges of a third class medical certificate.
First class[edit]
First class certificates are required for those intending to be pilot-in-command in an air carrier operation requiring an Airline Transport Pilot (ATP) certificate. Other operations, including those under Part 91, may require a first class medical for insurance purposes, although it is not a federal requirement in such cases.
To qualify for the first class medical certificate, pilots must meet the requirements for the third and second class certificates plus:
Heart Function: Electrocardiogram must show normal heart function once at age 35 and annually for those age 40 and over
For pilots under 40 years of age, first class medical certificates expire on the last day of the month they were issued, one year from the date of issue. The FAA introduced this rule on July 24, 2008.[23][24] For all others, they are valid until the last day of the month, six months after they were issued. The certificate holder may then only exercise the privileges of a second class medical certificate until the last day of the month, twelve months after the certificate was issued, thereafter the privileges of a third class medical until the last day of the month, twenty four months after the medical was issued ( FAA $61.23 (d-1-iii) ).
Attention: TDR Forum Junkies 
