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Two-Way Stop Controlled Intersections Two-way stop controlled intersections in which stop signs are used to assign the right-of--way, are the most prevalent type of intersection in the United States. At two-way stop-controlled intersections the stop-controlled approaches are referred as the minor street approaches and can be either public streets or private driveways. The approaches that are not controlled by stop signs are referred to as the major street approaches. The capacity of movements subject to delay are determined using the "critical gap" method of capacity analysis. Expected average control delay based on movement volume and movement capacity is calculated. A LOS designation is given to the expected control delay for each minor movement. LOS is not defined for the intersection as a whole. Control delay is the increased time of travel for a vehicle approaching and passing through astop-controlled intersection, compared with afree-Flow vehicle if it were not required to slow or stop at the intersection. A description of levels of service for two-way stop-controlled intersections is found in Table A-VI. Table A-VI: Description of Level of Service for Two-Way Stop Controlled Intersections LOS Description A Very low control delay less than 10 seconds per vehicle for each movement subject to delay. B Low convol delay greater than 10 and up to I S seconds per vehicle for each movement subject to delay. C Acceptable convol delay greater than I S and up to 25 seconds per vehicle for each movement subjett to delay. D Tolerable control delay Beater than 25 and up to 35 seconds per vehicle for each movement subject w delay. E Limit of tolerable convol delay greater than 35 and up to 50 seconds per vehicle for each movement subject to delay. F Unacceptable convol delay in excess of 50 seconds per vehicle for each movement subject to delay. Source: Highway Capacity Manua12000 J:\TJKM Appendices\LOS-HCM 2000.doc