Laws of Cricket 1980 Code - Law 19
1. The Boundary of the Playing Area
Before the toss for innings, the umpires shall agree with both captains on the boundary of the playing area. The boundary shall, if possible, be marked by a white line, a rope laid on the ground, or a fence. If flags or posts only are used to mark a boundary, the imaginary line joining such points shall be regarded as the boundary. An obstacle, or person, within the playing area shall not be regarded as a boundary unless so decided by the umpires before the toss for innings. Sight screens within, or partially within, the playing area shall be regarded as the boundary and when the ball strikes or passes within or under or directly over any part of the screen, a boundary shall be scored.
2. Runs Scored for Boundaries
Before the toss for innings, the umpires shall agree with both captains the runs to be allowed for boundaries, and in deciding the allowance for them, the umpires and captains shall be guided by the prevailing custom of the ground. The allowance for a boundary shall normally be 4 runs, and 6 runs for all hits pitching over and clear of the boundary line or fence, even though the ball has been previously touched by a fieldsman. 6 runs shall also be scored if a fieldsman, after catching a ball, carries it over the boundary. See Law 32 (Caught) Note (a). 6 runs shall not be scored when a ball struck by the striker hits a sightscreen full pitch if the screen is within, or partially within, the playing area, but if the ball is struck directly over a sightscreen so situated, 6 runs shall be scored.
3. A Boundary
A boundary shall be scored and signalled by the umpire at the Bowler's end whenever, in his opinion:
a. A ball in play touches or crosses the boundary, however marked.
b. A fieldsman with ball in hand touches or grounds any part of his person on or over a boundary line.
c. A fieldsman with ball in hand grounds any part of his person over a boundary fence or board. This allows the fieldsman to touch or lean on or over a boundary fence or board in preventing a boundary.
4. Runs Exceeding Boundary Allowance
The runs completed at the instant the ball reaches the boundary shall count if they exceed the boundary allowance.
5. Overthrows or Wilful Act of a Fieldsman
If the boundary results from an overthrow or from the wilful act of a fieldsman, any runs already completed and the allowance shall be added to the score. The run in progress shall count provided that the batsmen have crossed at the instant of the throw or act.
Note
1. Position of Sight-Screens
Sight-ccreens should, if possible, be positioned wholly outside the playing area, as near as possible to the boundary line.
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