Entity Type Description:
The System Chemical (SYS_CHEM) entity type is a composite of chemical validation tables from the Envirofacts component program office systems. It contains alternative names (i.e., synonyms) for chemical substances and the source of those alternative names.
- A chemical substance may be listed with more than one occurrence
of the same chemical name if it is so identified by more than one source.
- More than one chemical name may be identified by the same source,
using the same system chemical identification code.
- Data for this table are derived from chemical validation tables
in the EPA database systems. Data sources are:
- PCS - PRAMD table ID 160
- TRIS - OTSS table, table type TRCHEM
- RCRIS - Register of Lists (F and K waste codes), Dictionary of Chemical Substances (U and P waste codes), CFR 40 (D waste codes)
- AFS - Geo-Common Parameter Table, Pollutant Table
A unique record consists of a set of SYS_CODE, SYS_CHEMID and SYS_CHEMNAME.
- Every EMCIRN must exist in the CHEM_SUBST table.
- Multiple records may exist in CHEM_SUBST for the same EMCIRN.
- Multiple records may exist for the same SYS_CODE.
- Multiple records may exist for the same set of SYS_CODE and SYS_CHEMID.
Subject Area: Chemicals
Entity Type Definition Source:
Functional Design for the Envirofacts Master Chemical Integrator, September 1994.
Entity Type Attributes: