The official shall withhold the whistle until:
a. A goal is scored by the attacking team.
b. The ball goes out of bounds.
c. A player on the defending team gains possession of the ball.
d. The attacking team commits a foul or violation.
e. An injury occurs to a player on either team and is deemed by the official to be serious enough for an immediate whistle.
f. A player loses any of the required equipment in a scrimmage area, or a player is injured in a scrimmage area, and the official is required under the rules to blow the whistle.
g. The attacking team requests a team time-out.
h. The period ends.
i. A second defensive foul is committed, unless scoring play is imminent.