In mining regulations, reportable injuries are typically defined as injuries that are not classified as serious bodily injuries but still result in the worker being unable to perform their duties for a specified period. According to standard mining safety guidelines, such as those in the Indian Mines Act, a reportable injury involves an enforced absence from work for more than 72 hours. This threshold distinguishes reportable injuries from minor ones that require shorter recovery periods.
Thus, the correct answer is More than 72 hours.