Grading of the interference or disturbance on the intended task/procedure
| Event level | Observed effect |
| 1 | Potentially distracting source |
| 2 | Interference noticed by floating personnel |
| 3 | Floating member attends to non-case interference |
| 4 | Team member momentarily distracted from task |
| 5 | Team member pauses current task |
| 6 | Team member attends to distraction |
| 7 | Whole/part team momentarily distracted from task |
| 8 | Whole/part team attend to distraction |
| 9 | Flow of the task/procedure interrupted |
1=least, 9=most.