Okla. Stat. tit. 66 § 257
Current through Laws 2024, c. 453.
Seats and cushions shall be provided with a shock absorbent material initially at least three (3) inches in thickness and backrests shall be of a sufficient height to protect the neck and head from injuries. Seats in cupolas will be of the pullman or swivel type and those in bays shall be of the passenger reversible type. The backrests shall be provided with shock absorbent material initially of at least three (3) inches in thickness. Seats of a different design or materials may be used when such design or materials provide equal or better protection or comfort than those enumerated in this section.
Okla. Stat. tit. 66, § 257