3 foot lane- 8 2 E

Question
I understand if F3 is standing on the white portion of a double 1B,the batter-runner must stay in the outside (foul territory) 3 foot lane to touch the orange base to avoid being called out for interfering by being hit with a thrown ball.  Protected from a thrown ball interference by staying in the lane.  They call this a safe haven.    If F3 is on the orange portion of 1B, taking a throw from F2 in foul territory, the ASA book says that the batter runner CAN run in fair territory and if hit by a thrown ball, it is not interference.  The unclear thought I have is: (you're talking about 10 year old girls here)  If the batter-runner runs in the foul territory 3 foot lane as F3 is on the orange portion of 1B taking a throw from F2 in foul territory, is it interference because the batter runner's safe haven 3 foot lane switches to fair territory when the fielder at 1B decides to take a throw to the colored base?

I emphasized CAN because it seems they have a choice to avoid being called out for interference no matter what side the batter-runner is on when F3 takes a throw to the collored prtion of 1B.

Wow, my first year as an umpire and the more I learn, the less I realize I thought I knew!

Answer
Kevin,

I know exactly what you mean.  Look at it this way.  The runner doesn't have eyes in the back of their head.  

If the batter-runner is in the 3 foot (foul) lane, they are protected.  If the runner sees F3 move to the orange side to take a throw from foul territory, the BR can move to the fair side of the line and use the white side of the base without being put in jeopardy of committing interference.

I never have interference on a runner for staying in the running lane going to first.

Tom