RULES & REGULATIONS

128-5-1. Professional boxing, professional kickboxing. professional bare-knuckle fighting, and professional full-contact karate contests. (a) Each ring used for professional boxing, professional kickboxing, professional bare-knuckle fighting, or professional full-contact karate contests shall consist of an area that is no smaller than 16 by 16 feet square and no larger than 20 by 20 feet square when measured within the ropes. The apron of the ring platform shall extend at least two feet beyond the ropes. The ring platform shall not be more than four feet above the floor of the building or the grounds of an outdoor arena. Steps to the ring shall be provided for the use of the contestants and officials. 

(b )(1) Except as specified in paragraph (b )(2), each ring shall be fenced in with at least three ropes and not more than four ropes. Each rope shall be at least one inch in diameter. The ropes may be composed of Manila hemp, synthetic material, plastic, or any other similar material. Each rope shall be wrapped securely in soft material. If three ropes are used, the ropes shall extend in triple parallel lines at the heights of two feet, three feet, and four feet above the platform floor.  READ FULL DOCUMENT HERE