- ABNORMAL
In this case, malfunctioning or broken critical components require repair works which cannot be postponed till the next planned shutdown. Repair work could imply a total or partial stop of operations, but they could also be executed without shutdown
Repairs planned and performed during MAINTENTANCE should be classified as such. - COMMISSIONING
It covers activities with a high experimental and one-off characters, such as experiments at universities, or when developing prototypes, such as NASA did. A grey one is represented by those tests executed in industrial plants, following a great overhaul bringing considerable changes to components and installation. Depending on the specific case, these should be classified as COMMISSIONING or MAINTENANCE/REPAIR.
- DE-COMMISSIONING
In general, good event descriptions which do not mention out-of-normal conditions should be classified as NORMAL. However, some of the low-quality descriptions shall be labelled as UNKNOWN because there is a reasonable risk that critical info was omitted.
- MAINTENANCE
During a planned startup phase (after maintenance, repair, etc/). It implies (temperatures, pressures, flows) transient not experienced during NORMAL working conditions.
- NORMAL
In this case, the plant/equipment/etc. is in (partial) shutdown mode for planned interventions on the equipment, such as inspection & preventive maintenance and overhauls.
To this class belong also the cases of planned shutdowns for other reasons, such as strike and weekend suspension of operations. - REPAIR
Same as above, but when shutting down.
- SHUTDOWN
This is the opposite of the previous case, when a complex facility is dismantled at the end of its operating lifetime.
- STARTUP
This case covers the commissioning of the newly built facility/equipment/etc., as well as the previous period of construction and testing.
- TESTING
In general, good event descriptions which do not mention out-of-normal conditions should be classified as NORMAL. However, some of the low-quality descriptions shall be labelled as UNKNOWN because there is a reasonable risk that critical info was omitted.
