As stated in the National Risk Management Policy, "Chapters and Associations hosting Inter-Chapter Events shall collect emergency contact information from all non-host attendees, via method selected by the host Chapter or Association, no later than the beginning of the event, or at the time the attendee arrives, whichever comes later.
The host Chapter or Association shall maintain the emergency contact information for 24 hours past the completion of the Inter-Chapter Event. After 24 hours has passed, the host Chapter or Association shall promptly destroy the emergency contact information records, preferably by shredding the document(s), unless otherwise authorized by the attendee. Initiates may only be in attendance at Inter-Chapter Events that are hosted by their Collegiate Chapter."
A sample liability waiver form can be found here.