In order to prevent duplicate codes for the same item, clear descriptions should be included. Some codes must have documentation before they can be assigned:
- Parameter codes (PARAM) for chemicals require the CAS number
- Laboratory codes (RLABO) require the full address, website and EDMO code
- Intercalibration codes (ICCOD) require the final report of the intercalibration
OSPAR and HELCOM now request the reporting of the uncertainty of each parameter so reference materials are no longer required for newer data. Reference Material codes can be requested for legacy data and non-Regional Seas Convention data:
- Certified reference material codes (CRMCO) require the reference sheet with standard values
- Laboratory reference material standard values using the LRM template
