In this chapter, terms have the meanings stated in COMAR 10.21.17 and this regulation. Term Defined. “Residential crisis services (RCS)” means intensive mental health and support services that are: Provided to a child or an adult with mental illness who is experiencing or is at risk of a psychiatric crisis that would impair the individual's ability to function in the community; and Designed to prevent a psychiatric inpatient admission, provide an alternative to psychiatric inpatient admission, shorten the length of inpatient stay, or reduce the pressure on general hospital emergency departments.