This is the ValueSet that contains all the codes in US Core Status for Smoking Status Observation (http://hl7.org/fhir/us/core/ValueSet/us-core-observation-smoking-status-status) and US Core Status for Smoking Status Observation (http://hl7.org/fhir/us/core/ValueSet/us-core-observation-smoking-status-status). E.g. what you have to deal with if you get resources containing codes in either of them