A trigger locking system for a liquid applicator having a trigger with an opening is provided. The trigger locking system comprises trigger locking device configured to extend through the opening. The trigger locking device is configured to move, when actuated, between a defined locked position and a defined unlocked position. While the system is in a locked position, the trigger is nonactuable. While the system is in an unlocked position, the trigger is actuable such that, when actuated, a liquid is released from the liquid applicator.