It depends. At the City I work for, we have a Street Network entirely devoted to Emergency Response and in it we have a valid turn restriction - an intersection in the old part of town where fire apparatus cannot make the turn as oneroad intersects another at a very shallow angle and turns to one side (almost 180 degrees) cannot be made as the turning radius is too narrow for the fire apparatus.
So is your Network used for multiple purposes? Are the Turn Restrictions designed for normal vehicular traffic or for Emergency Response apparatus? If the turn restrictions are along the lines of "No Left Turn" due to traffic considerations, then you can probably not use those in Emergency Response.
Chris Donohue, GISP