diff --git a/ArtifactOntology.ttl b/ArtifactOntology.ttl
index cc80b4f..edfc8b6 100644
--- a/ArtifactOntology.ttl
+++ b/ArtifactOntology.ttl
@@ -987,7 +987,7 @@ cco:CuttingWeapon rdf:type owl:Class ;
 ###  http://www.ontologyrepository.com/CommonCoreOntologies/Dam
 cco:Dam rdf:type owl:Class ;
         rdfs:subClassOf cco:Artifact ;
-        cco:definition "An Artifact that is designed to impound surface water or underground streams."@en ;
+        cco:definition "A Material Artifact that is designed to impound surface water or underground streams."@en ;
         cco:definition_source "https://en.wikipedia.org/wiki/Dam" ;
         cco:is_curated_in_ontology "http://www.ontologyrepository.com/CommonCoreOntologies/Mid/ArtifactOntology"^^xsd:anyURI ;
         rdfs:label "Dam"@en .
@@ -2236,16 +2236,20 @@ cco:InfraredTelescope rdf:type owl:Class ;
 cco:Infrastructure rdf:type owl:Class ;
                    rdfs:subClassOf obo:BFO_0000040 ;
                    cco:alternative_label "Infrastructure"@en ;
-                   cco:definition "A Material Entity that bears one or more Functions in virtue of it being designed to provide some essential service or benefit that is necessary for an Organization to function."@en ;
+                   cco:definition "A Material Artifact that is composed of elements bearing Infrastructure Roles and is by itself sufficient to provide a planned service or benefit to some organization that maintains its elements."@en ;
                    cco:is_curated_in_ontology "http://www.ontologyrepository.com/CommonCoreOntologies/Mid/ArtifactOntology"^^xsd:anyURI ;
                    rdfs:label "Infrastructure System"@en .
 
 
 ###  http://www.ontologyrepository.com/CommonCoreOntologies/InfrastructureElement
 cco:InfrastructureElement rdf:type owl:Class ;
-                          owl:equivalentClass [ rdf:type owl:Restriction ;
-                                                owl:onProperty obo:RO_0000053 ;
-                                                owl:someValuesFrom cco:InfrastructureRole
+                          owl:equivalentClass [ owl:intersectionOf ( obo:BFO_0000040
+                                                                     [ rdf:type owl:Restriction ;
+                                                                       owl:onProperty obo:RO_0000053 ;
+                                                                       owl:someValuesFrom cco:InfrastructureRole
+                                                                     ]
+                                                                   ) ;
+                                                rdf:type owl:Class
                                               ] ;
                           rdfs:subClassOf obo:BFO_0000040 ;
                           cco:definition "A Material Entity that bears an Infrastructure Role."@en ;
@@ -2256,7 +2260,7 @@ cco:InfrastructureElement rdf:type owl:Class ;
 ###  http://www.ontologyrepository.com/CommonCoreOntologies/InfrastructureRole
 cco:InfrastructureRole rdf:type owl:Class ;
                        rdfs:subClassOf obo:BFO_0000023 ;
-                       cco:definition "A Role that inheres in the bearer of a Disposition such that the realization of that Disposition supports the functioning of an Infrastructure System."@en ;
+                       cco:definition "A Role that inheres in the bearer of a Disposition and has been assigned to an Infrastructure System such that the realization of that Disposition is sometimes part of the functioning of the Infrastructure System."@en ;
                        cco:definition_source "https://archive.org/details/economicsprincip00osul/page/n489/mode/2up"^^xsd:anyURI ;
                        cco:is_curated_in_ontology "http://www.ontologyrepository.com/CommonCoreOntologies/Mid/ArtifactOntology"^^xsd:anyURI ;
                        rdfs:comment "The disposition will typically be a function of an artifact, which is often designed to be part of some Infrastructure system. But not always. In some cases an entity may be repurposed to be an element of some Infrastructure. In those cases it is a capability of that entity that supports the functioning of the system."@en ;
@@ -2362,7 +2366,7 @@ cco:LandMine rdf:type owl:Class ;
 ###  http://www.ontologyrepository.com/CommonCoreOntologies/LandTransportationArtifact
 cco:LandTransportationArtifact rdf:type owl:Class ;
                                rdfs:subClassOf cco:Artifact ;
-                               cco:definition "An Artifact that is fixed in place and designed to enable the movement of Vehicles and Animals from one location to another via land."@en ;
+                               cco:definition "A Material Artifact that is fixed in place and designed to enable the movement of Vehicles and Agents from one location to another via land."@en ;
                                cco:is_curated_in_ontology "http://www.ontologyrepository.com/CommonCoreOntologies/Mid/ArtifactOntology"^^xsd:anyURI ;
                                rdfs:label "Land Transportation Artifact"@en .
 
@@ -5017,7 +5021,7 @@ cco:WasteManagementArtifactFunction rdf:type owl:Class ;
 ###  http://www.ontologyrepository.com/CommonCoreOntologies/WaterTransportationArtifact
 cco:WaterTransportationArtifact rdf:type owl:Class ;
                                 rdfs:subClassOf cco:Artifact ;
-                                cco:definition "An Artifact that is fixed in place and designed to enable the movement of Vehicles and Animals from one location to another via water."@en ;
+                                cco:definition "A Material Artifact that is fixed in place and designed to enable the movement of Vehicles and Agents from one location to another via water."@en ;
                                 cco:is_curated_in_ontology "http://www.ontologyrepository.com/CommonCoreOntologies/Mid/ArtifactOntology"^^xsd:anyURI ;
                                 rdfs:label "Water Transportation Artifact"@en .