That's not the question though is it, or thats not how I read the question anyway.
The area of the body with which it is possible to commit a handball extends from the outside of the shoulder to the end of the fingertips (fingernails included!).
I remember at our course, the instructor asked us to look at the seam between the sleeve and the body of the shirts we are wearing. Anything below the seam plays no part in the game of football, whether it be judging offside, handball or pushing/charging (unless you are GK).