The referee’s whistle - IRB Laws of Rugby Union 2012

Definitions
6.A

Referee
Before the match
6.A.1

Appointing the referee
6.A.2

Replacing the referee
6.A.3

Duties of the referee before the match
During the match
6.A.4

The duties of the referee in the playing enclosure
6.A.5

Referee altering a decision
6.A.6

Referee consulting with others
6.A.7

The referee’s whistle
6.A.8

The referee and injury
6.A.9

The ball touching the referee
6.A.10

The ball in in-goal touched by non-player
After the match
6.A.11

Score
6.A.12

Player sent-off
6.B

Touch judges and assistant referees
Before the match
6.B.1

Appointing touch judges and assistant referees
6.B.2

Replacing a touch judge or assistant referee
6.B.3

Control of touch judges and assistant referees
During the match
6.B.4

Where the touch judges or assistant referees should be
6.B.5

Touch judge or assistant referee signals
6.B.6

After signalling foul play
After the match
6.B.7

Player sent-off
6.C

Additional persons
6.C.1

Reserve touch judge or assistant referee
6.C.2

Those who may enter the playing area
6.C.3

Limits to entering the playing area

6.A.7 THE REFEREE’S WHISTLE

(a) The referee must carry a whistle and blow the whistle to indicate the beginning and end of each half of the match.
(b) The referee has the power to blow the whistle and stop play at any time.
(c) The referee must blow the whistle to indicate a score, or a touch down.
(d) The referee must blow the whistle to stop play because of an infringement or for an offence of foul play. When the referee cautions or sends off the offender, the referee must whistle a second time when the penalty kick or penalty try is awarded.
(e) The referee must blow the whistle when the ball has gone out of play, or when it has become unplayable, or when a penalty is awarded.
(f) The referee must blow the whistle when it would be dangerous to let play continue or when it is probable that a player has been seriously injured.