There is nothing mathematically 100% safe, the human meaning of the word inherently involves some kind of uncertainty.
Going for a test itself via car has a quite significant risk itself, should the doctor say that you shouldn't move out of this room, it's not safe?
Like even regularly used medicine has some slight chance of an adverse reaction, that's how minuscule side effects multiplied to human population times the number it's taken results in.
Guess what often has many orders of magnitude greater risk? Continuing having the disease you went to the doctor with in the first place, or having it lie undiscovered.
Going for a test itself via car has a quite significant risk itself, should the doctor say that you shouldn't move out of this room, it's not safe?
Like even regularly used medicine has some slight chance of an adverse reaction, that's how minuscule side effects multiplied to human population times the number it's taken results in.
Guess what often has many orders of magnitude greater risk? Continuing having the disease you went to the doctor with in the first place, or having it lie undiscovered.