diff --git a/ontology/saref4ehaw.ttl b/ontology/saref4ehaw.ttl
index e3077e177f0b4afebad70b4301bf4078a3606dbc..999cb06f234377bc472b63fc0082d874ce7b304c 100644
--- a/ontology/saref4ehaw.ttl
+++ b/ontology/saref4ehaw.ttl
@@ -1049,6 +1049,7 @@ s4ehaw:Helper rdf:type owl:Class ;
 
 ###  https://saref.etsi.org/saref4ehaw/Impairment
 s4ehaw:Impairment rdf:type owl:Class ;
+                  rdfs:subClassOf saref:State ;
                   rdfs:comment "Defined for users (that can in particular be patients) impairments modelling, e.g. aural impairment, skeletal impairment, ocular impairment, mobility impairment, intellectual impairment. Those non exhaustive impairments are compatible with the World Health Organization classification."@en ;
                   rdfs:label "Impairment"@en .