| Start Date | Start Time | End Date | End Time | Data Quality Metric |
|---|---|---|---|---|
| 05/21/1999 | 1413 | 05/27/1999 | 1819 | Incorrect |
| Subject: | SGP/AOS/C1 - Invalid absorption data |
| DataStreams: | sgpaosC1.a0, sgpaosauxC1.a0 |
| Description: | During the period noted, a valve position error with the 1-um/10-um impactor switching valve occurred. The result of this error was to invalidate all switched data. The software correctly inserted missing value codes in the nephelometer data, but the PSAP light absorption photometer for some reason reported a constant value over this period. |
| Suggestions: | Do not use PSAP data during this interval. |
| Measurements: | sgpaosauxC1.a0: more
sgpaosC1.a0: more |