In order to ensure the uniqueness of a person for the certification procedure of your divers, IFDI requires 4 elements of information from this person: First name, family name, date & place of birth. In comparison with other diving organizations who use only 3 elements, IFDI adds more confidentiality with the place of birth as a fourth element. Somehow, the place of birth is a kind of password meant for the concerned person with the advantage of never forgetting it. In accordance with the General Data Protection Regulation, please, make sure that your divers agree to be registered within the IFDI database.
In terms of liability, IFDI assumes full responsibility in all the content of its website. Your students don't need to sign a liability release regarding IFDI. Of course, on your side, you're free to request or not the signature of a liability release by your students, in tune with the laws of your country. You may also subscribe to a professional liability insurance at DAN, for example.
In terms of copyright, all the content of IFDI is copyright protected, but all the IFDI instructors are free to use any content of IFDI, as long as it is done in a positive way.