http://operations.nfl.com/media/1807/2015_nfl_rule_book_final.pdf
ARTICLE 9. DEAD BALL FOUL AND FOUL BETWEEN DOWNS.
A Dead Ball Foul is a foul that occurs in the continuing
action after a down ends, or a taunting foul that occurs at any time. The penalty for a Dead Ball Foul is enforced from the
succeeding spot, and the down counts.
A Foul Between Downs is a foul that occurs after the end of the down and after any continuing action resulting from the down,
but prior to the next snap or free kick. The penalty for a Foul Between Downs is enforced from the succeeding spot, and the
down counts, but it cannot be combined with a Live Ball Foul or a Dead Ball Foul to create a Multiple or Double Foul. A Foul
Between Downs is always enforced separately from any other foul. A foul against an official, regardless of when it occurs, is
always treated as a Foul Between Downs. See 12-3-1-h-pen.
Exception: If there is a personal, unsportsmanlike conduct, or taunting foul by either team following the end of the second
or fourth periods, the penalty yardage will be enforced on the second-half kickoff or the kickoff in overtime, unless it is part
of a Double Foul (See Section 5).
Item 1. Dead Ball Foul by Team A. If there is a Dead Ball Foul by Team A after a down in which Team A has made a first
down, after enforcement of the penalty it will be first-and-10 for Team A. If there is a Foul Between Downs after a down in
which Team A has made a first down, after enforcement of the penalty it will be first-and-25 for Team A.
Item 2. Dead Ball Fouls by Both Teams. Dead Ball Fouls by both teams are offset at the succeeding spot, and the down
counts, but any disqualified player or players must be removed pursuant to Rule 5, Section 2, Article 7.
Item 3. Live Ball and Dead Ball Fouls. Live Ball Fouls and Dead Ball Fouls combine to create Double Fouls or Multiple Fouls,
and all customary rules for enforcement apply.
Exceptions:
(1) If there is a 5-yard vs. 15-yard Double Foul on the last play of a half, and the 15-yard penalty is for a Dead Ball,
personal, unsportsmanlike conduct, or taunting foul by either team, the penalty yardage will be enforced on the
second half kickoff or the kickoff to start overtime. There will be no extension of the period. See 14-5-1-Exc.
(2) If the scoring team commits a Dead Ball Foul after a score, and its opponent’s Live Ball Foul is not for
unsportsmanlike conduct or unnecessary roughness, the opponent’s foul is disregarded, the score counts, and the
offensive team’s Dead Ball Foul is enforced on the kickoff. If the opponent’s foul is for unsportsmanlike conduct or
unnecessary roughness, the score counts, and both fouls are enforced on the kickoff.
Notes:
(1) When a foul occurs simultaneously with the ball becoming dead, it is considered to be a Dead Ball Foul.
(2) The succeeding spot for a foul that occurs after a touchdown and before a whistle for a Try is the next kickoff.
(3) The time between downs includes the interval during all timeouts (includ