In this chapter, the definitions in COMAR 14.31.05 and 14.31.06 apply, and the following terms have the meanings indicated. Terms Defined. “Developmental Disabilities Administration” means the Developmental Disabilities Administration of the Maryland Department of Health. “Infant” means a child younger than 24 months old. “Locked door isolation” means the involuntary restriction of a child from others for a period of time to a designated area from which the child may not leave, for the purpose of providing the child with an opportunity to gain behavioral control.