Laws of Cricket 1980 Code - Law 11
1. Before the Start of a Match
Before the start of a match, complete covering of the pitch shall be allowed.
2. During a Match
The pitch shall not be completely covered during a match unless prior arrangement or regulations so provide.
3. Covering Bowlers' Run-Up
Whenever possible, the bowlers' run-up shall be covered, but the covers so used shall not extend further than 4 feet/1.22m in front of the popping crease.
Notes
1. Removal of Covers
The covers should be removed as promptly as possible whenever the weather permits.
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