| Year | Date | Day of Year | Type and Results |
|---|---|---|---|
| 1990 | Dec. 31 | 365 | Telescope safes (FGE 3 bit flip); UV flood. |
| 1991 | Jan. 02 | 002 | Mini-low-temperature decon. |
| 1991 | Jan. 26 | 026 | De-ice decon (-82C) - failed to remove daisies. |
| 1991 | Jan. 28 | 028 | Mini-low temperature (-20C) - removed daisies; got measles. |
| 1991 | Jan. 29 | 029 | Low temperature decon (-15C) - removed measles. |
| 1991 | May 02 | 122 | PSEA hardware safemode (CCDs at -35 for 80 hrs); measles. |
| 1991 | May 08 | 128 | Hot-junction decon (+12C) - removed measles. |
| 1991 | Jul. 03 | 184 | WIDLE turned WFC TEC off for 7 hrs (WFC reached -25C) - measles. |
| 1991 | Jul. 05 | 186 | Flash decon (+6C) - removed measles. |
| 1992 | Feb. 03 | 034 | Flash decon - restored UV transmission, removed scattering; left measles. |
| 1992 | Feb. 04 | 035 | Flash decon (same as day 034) - measles still present. |
| 1992 | Mar. 03 | 063 | Hot junction decon - measles still present. |
| 1992 | Mar. 08 | 068 | Flash decon - measles still present. |
| 1992 | Aug. 07 | 220 | Flash decon (CCDs +3.5C to +8.5); persistent measles remain. |
| 1993 | Aug. 02 | 214 | Flash decon (CCDs +2 to +6C, except WF1 only -4C). |