A queue consists of three components, namely “Uniform”, “Random”, and “Oversaturation”. Although the TRANSYT analysis takes account of all three components, the graphs display only the “Uniform” component. Therefore, one cannot use the graphs to predict blocking problems.
Alongside each graph is the “UMMQ” value, i.e. the “Uniform Mean Maximum Queue”. This figure will always be less than the “MMQ” value given elsewhere in the TRANSYT output, which includes all three components of queue. The “MMQ” value should always be used as a basis for predicting queue blocking, and even then should make allowance for variations from day to day