8 minutes1 unit
23 minutes2 units
38 minutes3 units
53 minutes4 units
68 minutes5 units
83 minutes6 units

Check with your facility for specifics.

  • Although called the rule of 8’s, your facility may require a minimum amount of treatment time to be billable for 1 unit. For example, my facility requires at least 15 minutes of treatment for 1 unit.
  • 1 evaluation = 3 units


  • Use your watch’s stopwatch to time each session then write it down on your scratch paper.