R.I. Gen. Laws § 4-1-3.1

It is unlawful for any veterinarian or owner, as defined in § 4-1-1, or any agent of a veterinarian or owner, or any other person to destroy any animal by the use of a high altitude decompression chamber. When carbon monoxide is used as a euthanizing agent, only one animal is placed in the chamber. Violation of this section is punishable by a fine of five hundred dollars ($500).