Entity Type: SUBST_REL
Entity Type Description:
The SUBS_REL (Substance Relationship) entity type is a cross reference of group substances (i.e.. categories, mixtures, non-specific isomers) with their component substances.
Relationships:
Every record in this entity type is unique. In addition:
- An EMCIRN may exist as either a GROUP_EMCIRN or a COMPONENT_EMCIRN in different records.
- Multiple COMPONENT_EMCIRN may exist for one EMCIRN in CHEM_SUBST.
- Multiple GROUP_EMCIRN may exist for one EMCIRN in CHEM_SUBST.
- EMCIRN in CHEM_SUBST is a foreign key for GROUP_EMCIRN and COMPONENT_EMCIRN.
Subject Area: Chemicals
Entity Type Definition Source:
Functional Design for the Envirofacts Master Chemical Integrator, September 1994.
Entity Type Attributes:
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