Is there any tolerance on deformed steel reinforcement bar diameter?

The tolerance may be on the reinforcement bar mass per unit length, While when we come to the bar diameter which is directly related to the crossectional area which is the direct result during structural design, and the engineer gives the nominal reinforcement diameter required for the structure after cross checking the minimum and maximum reinforcement bar area need to be used for specific concrete structural element , hence there is no way to go for extra reduction  or addition from the specified nominal bar diameter /total bar area required / however we can use equivalent bar area during construction.