Project teams sometimes claim a very low control factor (CF). For example, they\'ll claim CF = 0.5, corresponding to a water savings of 50%, just from the use of controllers or timers. (Other water savings, such as the good distribution uniformity that results from head to head coverage, or the use of drip irrigation, is already accounted for in other parts of the calculator.) Is this water savings achievable from these devices? Or is there a minimum CF that can be claimed?
Typical control factors are 0.7 to 0.9 (corresponding to water savings of 30% to 10%, respectively.) If a project team wishes to claim a control factor less than 0.7, they must submit the calculation supporting the control factor for review and approval.
Updated 10/1/13 for rating system applicability.