| Inbound Relationships | Type | Active | Source | Characteristic | Refinability | Group | 
| Implantable valve | Is a | False | Valve | Inferred relationship | Existential restriction modifier |  | 
| Endoscopic valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Intravenous line stopcock | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Demand valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Pressure relief valve, reusable | Is a | False | Valve | Inferred relationship | Existential restriction modifier |  | 
| Pressure relief valve, single-use | Is a | False | Valve | Inferred relationship | Existential restriction modifier |  | 
| Positive end expiratory pressure valve, reusable | Is a | False | Valve | Inferred relationship | Existential restriction modifier |  | 
| Pulmonary function valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Tracheostomy tube speech valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Cardiopulmonary bypass system valve, unidirectional flow/pressure control | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Ploss valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Tracheoesophageal speech valve, non-indwelling | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Cardiotomy reservoir vacuum relief valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Tracheoesophageal speech valve, indwelling | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Positive end expiratory pressure valve, single use | Is a | False | Valve | Inferred relationship | Existential restriction modifier |  | 
| Surgical irrigation/aspiration handpiece control valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Hazardous gas safety valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Non-rebreathing valve, reusable | Is a | False | Valve | Inferred relationship | Existential restriction modifier |  | 
| Cardiopulmonary resuscitation inspiratory impedance valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Fire safety valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Non-rebreathing valve, single-use | Is a | False | Valve | Inferred relationship | Existential restriction modifier |  | 
| Medical gas regulator | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Expiratory valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Catheter flush valve, continuous | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Needleless valve-connector | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Cardiopulmonary resuscitation impedance valve, inspiratory/expiratory | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Tracheoesophageal speech valve occluder, valved | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Tracheoesophageal speech valve occluder, non-valved | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Blood pressure cuff multichannel valve unit | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Pleural drainage valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  | 
| Cerebrospinal fluid shunt valve | Is a | True | Valve | Inferred relationship | Existential restriction modifier |  |