This code system http://hl7.org/fhir/flag-priority-code defines the following codes:

Code Display Definition
PN No alarm No alarm.
PL Low priority Low priority.
PM Medium priority Medium priority.
PH High priority High priority.
<status value="active"/> <experimental value="false"/> <description value="This value set is provided as an exemplar. The value set is driven by IHE Table B.8-4: Abnormal Flags, Alert Priority."/> <jurisdiction> <coding> <system value="http://unstats.un.org/unsd/methods/m49/m49.htm"/> <code value="001"/> <display value="World"/> </coding> </jurisdiction> <caseSensitive value="true"/> <content value="complete"/> <concept> <code value="PN"/> <display value="No alarm"/> <definition value="No alarm."/> </concept> <concept> <code value="PL"/> <display value="Low priority"/> <definition value="Low priority."/> </concept> <concept> <code value="PM"/> <display value="Medium priority"/> <definition value="Medium priority."/> </concept> <concept> <code value="PH"/> <display value="High priority"/> <definition value="High priority."/> </concept> </CodeSystem>