| Subject | Scope | Notes |
| depot | IN | depicted by depot map |
| depot building | IN | included in the depot map |
| depot building description | IN | describes a depot building |
| depot building maintenance | IN | a system operation |
| depot building management operations | IN | available system operations |
| depot building neighbor | IN | a relationship between depot buildings |
| depot company regulation | IN | a system operational policy |
| depot drum allocation report | IN | a system output |
| depot drum inventory | IN | maintained by the system |
| depot governors | OUT | stakeholders who define operational policies |
| depot manager | IN | a system user and depot staff member |
| depot management system | IN | the system |
| depot map | IN | describes the spatial layout of the depot buildings |
| depot monitoring | IN | depot manager responsibility |
| depot staff building | IN | houses staff members |
| depot staff member | IN | work in the depot |
| depot status report | IN | reports the state of the depot |
| depot storage building | IN | stores drums containing hazardous chemicals |
| depot storage building description | IN | describes a storage building |
| depot vulnerability | IN | a system operational policy concern |
| drum | IN | contains a hazardous chemical |
| drum contents | IN | the measurable content of a storage drum |
| drum count | IN | a count of drums |
| drum handler | IN | a depot staff member |
| drum identifier | IN | identifies a storage drum |
| drum identification label | IN | describes a storage drum |
| drum load | IN | some drums |
| drum load collection | IN | a system state / activity |
| drum load collection order | IN | accepted during drum load collection |
| drum load collection manifest | IN | produced during drum load collection |
| drum load delivery | IN | a system state / activity |
| drum load delivery manifest | IN | accepted during drum load delivery |
| drum load discrepancy report | IN | produced during drum load delivery |
| drum load returned drum report | IN | produced during drum load delivery |
| drum storage | IN | a capability of a storage building |
| drum storage capacity | IN | the remaining capacity of a storage building |
| drum storage license | IN | describes the empty capacity a storage building |
| drum storage limit | IN | the empty capacity of a storage building |
| drum storage space allocation | IN | a system responsibility |
| EPA | OUT | stakeholder which defines operational policies |
| EPA hazardous chemical storage regulation | IN | defines system operational policies |
| EPA hazard type | IN | describes a kind of hazardous chemical |
| hazardous chemical | IN | stored within a storage drum |
| hazardous chemical storage | IN | drums within a storage building |
| hazardous chemical storage facility | IN | depicted by depot map |
| hazardous chemical storage license | IN | individual storage building licenses |
| loading bay | IN | included in the depot map |
| loading bay clerk | IN | a system user and depot staff member |
| loading bay operations | IN | system operations |
| safety compliance | IN | a system operational policy |
| safety regulation | IN | a system operational policy |
| safety violation | IN | a system operational policy concern |
| truck | OUT | delivers or collects drums |