The Medical Card Guidelines state that
Applicants whose weekly incomes are derived solely from Social Welfare allowances/ benefits or Health Service Executive allowances, which are in excess of the Income Guidelines (either at first or on renewal), should be granted a Medical Card.
Training courses (e.g FAS, VTOS, etc) would not be considered Social Welfare income.
There are some exemptions for persons on training courses.
If a person who has been granted a medical card because they are on SW takes up a Government training scheme (e.g. FAS), they retain the card for the duration of the course. If the person doesn't have a medical card, but would have qualified had they applied prior to starting the course, the card will be granted for the duration of the course.
For example, a person on JB who didn't apply for a card but who would have qualified if he/she had, would be granted a card while on the training course.
Persons aged 16 years must make a separate application - if the parents qualify for a card, then the 16 yo will get a card automatically. If the parents don't qualify for a card, then the 16 yo is means-tested to determine eligibility.