The intervention under investigation is a simple label applied to the blood bag in such a way to cover (obstruct entry) the "ports" used to administer blood. The label will be applied to units of crossmatched red cells only. The position of the label will require that the user remove the label to administer the red cells. The label will state: "STOP: Check the patient's wristband". The wording will be translated to the appropriate language as necessary.