34 C.F.R. § 300.29
(a) Native language, when used with respect to an individual who is limited English proficient, means the following:
(b) For an individual with deafness or blindness, or for an individual with no written language, the mode of communication is that normally used by the individual (such as sign language, Braille, or oral communication).
(Authority: 20 U.S.C. 1401(20))