Null Data Reason Code¶
A code explaining why no sample, blank, or quality assurance assessment value was reported.
Must be a valid AQS Null Reason Code.
Must not be valued if the Sample Measurement is valued.
Must be valued if the Sample Value or Monitor Assessment is null/empty.
May not be valued on an RD record that also has an exclusion qualifier submitted.
Allowable values: https://aqs.epa.gov/aqsweb/documents/codetables/qualifiers.html