The first cooling break has been observed at the Brazil 2014 World Cup. The Ref blew his whistle in the 30th minute to call for a cooling break. If you were wondering why the rule is simple when the heat condition of a match is to high a ref can call for a cooling break.
However the Mexicans have been on top of their game in the first 30mins with the orange boys recording zero shots on target. The venue of the match's weather condition is 38 degrees celcious. That can give you a clue to why the ref had to cal for a break.
