Are there any physical, mental, or health-related medical conditions that could permanently exclude someone from going into space?
Do the criteria differ from one country's (government sponsored or private) program to another?
For NASA, candidates must be able to pass the long-duration space flight physical. Height, blood pressure, and vision are three of the physical requirements included in this test. From their website:
The Roscosmos requirements for the professional cosmonaut candidates are published here. The google translation seems to be intelligible.
It includes the list of medical areas of inspection:
- internal organs inspection;
- neuropsychiatric inspection;
- surgical inspection;
- ophthalmological inspection;
- otorhinolaryngologic inspection;
- dental inspection;
- functional inspection;
- gynecological examination (for women);
- psychiatric inspection;
as well as the list of assays required (all kinds of blood tests, feces, urine, 12-lead ECG, etc etc etc).
And, in particular, the set of general anthropometric requirements.
Anthropometric data (the maximal allowed values):
- height (150-190 cm);
- height in the sitting position (80-99 cm);
- weight (50-90 kg);
- foot length (29.5 cm);
- shoulders (52 cm);
- distance between the armpits (45 cm);
- hip width in the sitting position (41 cm).