official
Video "A Guide to american football"

The Officials
The game shall be played under the supervision of four, five, six or seven officials.
Four: a referee, an umpire, a linesman and a line judge
Five: a referee, an umpire, a linesman, a line judge and a back judge
Six: a referee, an umpire, a linesman, a line judge, a field judge and a side judge
Seven: a referee, an umpire, a linesman, a line judge, a back judge, a field judge and a side judge.
Responsabilities
IAlteh official is responsible for knowing the yardage to gain and the number of the down, granting timeouts, declaring the ball dead, starting the clock on free kicks, determining scores, using proper signals, and mastering NCAA or NFL playing rules. Officials shall use the Football Officials Manuel published under the jurisdiction of the Collegiate Commissioners Association.

Designated officials shall report the position or number of the player who fouled to the player's coach.

All officials are responsible for decisions involving the application of rule, its interpretation or enforcement.

Officiating crew members are required to meet in theur dressing quarters at least one our and 45 minutes before game time for discussin on rules and officiating mechanics.

Each official shall drop a marker and record each foul he observes.

Each official has specific duties but has equal juruduction in matters of judgment.

Equipment
Officials shall wear: a whistle, a marker to designate fouls, a marker to record important field locations, a game card for recording fouls and down recorder.
Referee
Basic Responsabilitites

The referee has general oversight and contro of the game and will conduct a thorought pregame conference for the crew.
The referee is the sole authority for the score, and his decisions upon rules and other matters pertaining to the game are final.
The referee shall declare the ball ready for play after determining the officialsare ready and shall direct the clock started on the ready for the play or snap. The referee shall time 25 second count when it is not assignated to another official or instadium timer. In addition, he will count the number of offensive players.
The referee shall administer penalties, being sure that both captains understand the procedure and outcome. He will check the umpire's penalty enforcement. The referee, if equipped with a microphone, shall announce the number of the player committing the foul.
The referee tests and selects the game balls. He inspects the playing enclosure and reports irregularities to game management, coaches and other officials.
The referee shall notify both head coaches if visual timing devices become inoerative and of any disqualifications.
The referee shall observe the relative position of the ball and the line to gain and determine if new series of downs is awarded.
The referee is responsible for the number of timeouts charged to each tema, and shall notify the field captain and head coach when that team has used its final timeout of half or extra period.

Position

The initial position of the referee on scrimmage plays is behind and to the side of the offenseve backfield, where he observes shifts, legality of blocking and play behind the neutral zone involving the ball. The referee is responsible for coverage of the quarterback and the kicker and holder on scrimmage kicks.
The position of the referee on free kicks is in the area of the deep receivers

Umpire
Basic Responsabilitites

The umpire has juridiction over player equipment.
The umpire is responsible for line play on both sides of the neutral zone, legaly of linemen downfield, defensive signals, and wether passes and kicks cross the neutral zone. He also is responsible for the legality of the snap, counting offensive players and correctly enforcing penalties.
The umpire will remind the referee of time remaining in each period.

Position

The initial position of the umpire on scrimmage plays is five to seven yards beyond the neutral zone, where he adjusts his position to prevent interference with player movement.
The umpier's position on free kicks is with the kicker. As a member of a four man crew, he is positioned on the press box sideline on the kicker's restraining line.

Linesman
Basic Responsbilities

The linesman is reponsible for the operation of the line to gain indicator and down indicator. He instructs a crew consisting of a minimum of two assistants and a third person who operate the line to gain and down indicators outside the sideline opposite the press box. The down indicator marks the football's position.
The linesman has juridiction over the neutral zone and infractions of the scrimmage formation.
The linesman indicates forward progress to the referee or umpire and keeps count of the downs.
As the ball passes the neutral zone on his side of the field, the linesman determines the legality of play around the ball.

Position

On scrimmage plays, the linesman's initial position is in the neutral zone opposite the press box at the sideline.
The initial position of the linesman on kickoofs in a six or seven man crew is at the goal line of the receiving team, opposite the press box. As a member of a four or five man crew, the linesman's position is at the receiving team's restraining line, opposite the press box.

Line Judge
Basic Responsbilities

The line judge has jurisdiction over the neutral zone and infractions of the crimmage formation.
The line judge instructs an optional alternate down indicator operator who assists in making the ball's position.
When a member of a four man crew, the line judge is responsible for timing the game, supervising the game clock operator and the ball persons, and counting defensive players.
The line judge indicates forward progress to the umpire and referee.
As the ball passes the neutral one on his side of the field, the line judge determines legality of play around the ball.

Position

On scrimmage plays, the initial position of the line judge is in the neutral zone on the press box side of the field at the sideline.
As a member of a four man crew, the line judge shall ssume initial position 15 to 20 yards deep in the defensive backfield during scrimmage kick situations.
The initial position of the line judge on kickoffs in a four, six or seven man crew is at the goal line of the receiving team on the press box sideline. As memeber of a five man crew, the line judge is positioned at the restraining line of the kicking team.

Field Judge
Basic Responsbilities

The field judge is responsible for observing eligible receivers, kicks and passes on his side of the field.
The field judge is responsible for assisting the back judge in counting defensive players and ruling on the ball's status in his area.
The field judge is responsible for the ball persons on his side of the field in a six or seven man crew.

Position

During scrimmage plays as a member of a six or seven man crew, the field judge is positioned approximately 20 yards behind the defensive side of the neutral zone on the press box side of the field with his initial position at the sideline.
On free kicks in a six or seven man crew, the field judge is positioned on the sideline at the receiving team's restraining line.

Side Judge
Basic Responsabilities

The side judge is responsible for timing the game and observing eligible receivers, kicks and passes on his side of the field.
The side judge rules on the status of the ball in his area.
The side judge is responsible for the ball persons on his side of the field in a six or seven man crew.

Position

On scrimmage plays, the side judge in a six or seven man crew is positioned approximately 20 yards deep on the defensive side of the neutral zone on the sede of the field opposite the press box with his initial position at the sideleine.
On free kicks, the side judge in a seven man crew is at the receiving team's restraining line on the lineman's sideline. In a six man crew, the side judge is at the kicking team's restraining line.
On try downs and field goals, the side judge in a seven man crew assists the umpire by serving as a "double" umpire.

Back Judge
Basic Responsbilities

The responsabilities of the back judge include counting the defensive team, timing the 25 second count, ruling on long passes and kicks, and the status of the ball in his area.
The back judge observes eligible receivers leaving the neutral zone.
The back judge has the responsability for the ball persons in a five man crew.

Position

On a scrimmage plays, the back judge in a five or seven man crew is positioned approximately 20 to 25 yards beyond the neutral zone and deeper than the defensive backfield. The lateral posision is determined by the use of a field judge and side judge.
On free kicks, the back judge in a seven man crew is at the sideline on the restraining line of the kicking team on the press box side. As a member of a five man crew, he is positioned at the 10 yard line on the press box sideline.