IR should provide a registration arrangement for DA Persons in a separate site and issue an ID number for them.By using the ID while booking on line the ticket should have the image (Photo)of the DA Person with all details.Then all the problems will get solved.
The first time registration may be done at the Divisional HQ by medical team and the registration may be renewed once in 3 or 5 years. If; the Govt; really interested in the welfare of the DA. this is not a big job for IR.