The following are the changes to the ICC's playing conditions that will come into effect for all international series beginning from September 28, 2017.
Each team can name six substitutes (previously it was four) in Test cricket.
There are no changes to the permitted width and length of a cricket bat, but the thickness of the edge can be no more than 40mm, and the thickness of the bat must not exceed 67mm at any point. Umpires will have a gauge to check that bats meet the new regulations.
The ICC has okayed the use of bails tethered to the stumps to prevent injuries caused by bails flying at wicketkeepers and fielders after the stumps have been broken. The mechanism used to tether the bails must not interfere with their ability to be dislodged; the implementation of such a system is at the discretion of the host board.
In Test cricket, an interval will be taken if a wicket falls within three minutes of the interval. Previously it was two minutes.
In T20 internationals, if an innings is reduced to less than 10 overs, the maximum quota of overs per bowler shall not be less than two: meaning that if a match is reduced to five overs a side, two bowlers will be able to bowl two overs each.
For boundaries, airborne fielders making their first contact with the ball will need to have taken off from inside the boundary, otherwise a boundary will be given. A boundary will also be given if a fielder in contact with the ball makes contact with any object grounded beyond the boundary, including another fielder.
If the ball bounces more than once after being delivered by the bowler and before it reaches the popping crease of the batsman, it will be called a no-ball. Previously a ball was allowed to bounce twice. If the ball lands off the pitch, then the umpire will signal a no-ball. If a fielder intercepts the delivery before it reaches the batsman, the umpire will call no-ball and dead ball.
Any byes or leg byes scored off a no-ball will now be scored separately. The bowler will have one no-ball put against his/her name, and the other extras will be scored as byes and leg byes. Previously, byes and leg byes scored off no-balls were scored as no-balls.
If a batsman grounds his/her bat or part of his/her body behind the crease while regaining his/her ground before the stumps are broken, and then if he/she inadvertently loses contact with the bat, or if the grounded part of his/her body becomes airborne - while running or diving - when the stumps are broken, he/she shall not be run out or stumped.
An appeal can be withdrawn, or the umpires can recall a dismissed batsman, at any time before the ball comes into play for the next delivery. Previously, a batsman could not be recalled once he/she had left the field.
For a catch on the boundary to be legal, a fielder making contact with the ball must either be grounded inside the boundary or his/her last contact with the ground before first touching the ball must have been inside the boundary.
A batsman can be caught, run-out, or stumped even if the ball makes contact with a helmet worn by the fielder or wicketkeeper.
The handled-the-ball dismissal has been removed and included under the obstructing-the-field category.
There are several tweaks to what now constitutes unfair play. If the fielding side tries to deliberately distract or deceive the batsman - through mock fielding for example - after he/she has received the ball, the umpires can penalise them. If a bowler bowls a deliberate no-ball, he/she can be removed from the attack for the rest of the innings. A batsman cannot take strike so far outside the crease that he/she is standing in the protected area of the pitch, just like bowlers are not allowed to follow through on the protected area. A catch-all law has now been introduced to give umpires the power to deal with conduct they believe is unfair but is not covered elsewhere in the laws.
A player can now be sent off the field by the umpire for the rest of a match for serious misconduct. This will apply to most Level 4 offences, with with Level 1-3 offences continuing to be dealt with under the ICC Code of Conduct.
If an umpire's decision is referred to the TV umpire by a team, and the on-field decision remains unchanged because the DRS shows "umpire's call", the team will not lose the review.
Because teams will not lose a review for "umpire's call", they will not have their two unsuccessful reviews replenished after the first 80 overs of the innings in a Test. They will have only two unsuccessful reviews for the entire innings. The DRS will now be used in T20 internationals as well - teams will have one unsuccessful review per innings.