14 CFR § 382.115 - What requirements apply to on-board safety briefings?
As a carrier, you must comply with the following requirements with respect to on-board safety briefings:
(b) You may offer an individual briefing to any other passenger, but you may not require an individual to have such a briefing except as provided in paragraph (a) of this section.
(c) You must not require any passenger with a disability to demonstrate that he or she has listened to, read, or understood the information presented, except to the extent that carrier personnel impose such a requirement on all passengers with respect to the general safety briefing. You must not take any action adverse to a qualified individual with a disability on the basis that the person has not “accepted” the briefing.
(d) When you conduct an individual safety briefing for a passenger with a disability, you must do so as inconspicuously and discreetly as possible.