This code system http://hl7.org/fhir/v2/0617 defines the following codes:

CodeDisplayComments
CClassificationIdentifies an address used for the purpose of demographic classification or searching. Such addresses frequently contain insufficient information to be used as mailing or visit addresses. For example, they may only indicate country and postal code, with
MMailingIdentifies an address for mail correspondence from a healthcare provider as stipulated by the subject.<p>For example, under the tenets of certain privacy regulations, it is exclusive to the patient and is typically maintained at the encounter or visit lev
VVisitIdentifies an address at which the individual is physically located and may be visited.