Rule 4 – Live Ball, Dead Ball

SECTION 1. Live Ball – Dead Ball

ARTICLE 1. Dead Ball Becomes Alive

For the next down the ball shall be put in play at the spot midway between the side lines, laterally in line with the spot where the ball was when it became dead by rule, or at the spot where the ball has been placed following completion of an accepted penalty or to award a new series.
After a dead ball is ready for play, it becomes a live ball when it is legally snapped.
A ball snapped before it is ready for play or is illegally snapped remains dead.
A foul before the ball is snapped (delay of game, encroachment, false start, disconcerting signal, illegal blitzer signal) will cause the ball to remain dead.

ARTICLE 2. Live Ball Becomes Dead

A live ball becomes dead and an official shall sound his whistle when:
a. A ball touches anything out of bounds.
b. The runner goes out of bounds.
c. Any part of the runner’s body, except his hand or foot, touches the ground.
d. A runner simulates placing his knee on the ground.
e. A pass or fumble strikes the ground.
f. A teammate of the fumbler catches the ball.
g. A player becomes in possession of the ball with fewer than 2 flags.
h. The flags of a player in possession of the ball are not positioned correctly and the player himself is responsible for it.
i. A touchdown, touchback, safety or successful try occurs.
j. A foul which causes the ball to become dead (e.g. illegal kick or delay of pass) occurs.
On an inadvertent whistle by an official, the ball becomes dead and the team in possession may elect either to put the ball next in play where it was declared dead or to replay the down.