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Technical Procedures Calculate the volume-to-capacity ratio for each movement and combined movement by dividing the adjusted volumes by the capacities. For combined movements, use the combined volumes divided by the combined capacities. TABLE 9 Lane Capacities~ Lane Type 2-Phase 3-Phase 4+-Phase Exclusive Lane 1,800 1,720 1,650 Shared Lane 1,800 1,720 1,650 Dual Turn Lanes:-~ 1,636 1,564 1,500 Triple Turn Lanes:" 1,565 1,496 1,435 Capacities for single lane. If multiple lanes are provided, capacity in the table is multiplied by number of lanes to obtain total capacity for movement group. Can include one shared lane (e.g. one exclusive left, plus one shared through left is considered dual turn lane). Assumes 45%-55% lane split. Assumes lane use 15% higher in the most used lane. STEP 7: Determine Critical Volume-to-Capacity Ratios Determine the highest total conflicting volume-to-capacity ratios for both the north-south and east-west directions. For a non-split phased direction, the highest total of the right-turn or the through (or through plus right-turn if no exclusive right-turn lane exists) plus the opposing left-turn volume-to-capacity ratios are chosen. For a split phased direction, the highest volume-to-capacity ratio from each of the approachs is chosen. Free right turns are not included in the calculation since they are not under signal control. Circular 212 does not clearly indicate how the critical movements are to be selected for single lane approaches (that is, when all right, left and thru movements are made from single approach lane). Under the Circular either the approach with the highest volume or both approaches could be designated as the critical movement. As pan of the Level of Service method adopted by the CCTA, however, both approaches should be considered critical movements.