Chris,
If a task does not rely on colour for safe decision making then there is no need to classify as colour safe/unsafe.
Driving and flying do not rely on colour. Colour is used but its redundant. There is no colour testing for drivers because colour deficient drivers are able to make the same safety decisions as colour normal drivers - just like pilots.
In marine navigation there are tasks where colour is the only clue and thus it is sensible to determine if someone is safe and unsafe.