By default, the rule stays active for 24 hours. However, you can adjust it to match your employee work schedule. For example, you can have the rule active during work hours but disable it during the employee lunch breaks.
You can change the rule’s schedule when creating or editing a rule. The scheduler is located on the rule’s General tab, under the When is this rule active? section:
To change when the rule is active, drag the two Circles 
to adjust the time. You can click the Plus (+) and Minus (–) buttons to add/remove additional time slots.
Please note that not all rule configurations support defining a rule schedule. For example, many of the agent schedule rules (where the Rule Category is set as Agent Schedule) are instead enforced based on the employee's schedule.