The 2010 American Heart Association (AHA) for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science has changed the basic life support (BLS) sequence from “A-B-C” to “C-A-B.” The AHA explained that this change may shorten the initiation time for chest compressions. In this study, the 2010 AHA guidelines for BLS (2010-BLS) were studied through a simulation program and practiced on a manikin. The time saved in initiating initial chest compressions was calculated, and the significance of the new guidelines was evaluated.Forty health care providers who had undergone both the BLS guidelines of 2005 (2005-BLS) and the 2010-BLS programs were targeted in this study. The following items were measured: time spent on rescue breathing, including setting up of ventilation equipment; time taken to initiate chest compressions; and time taken to initiate chest compressions without performance of rescue breathing because of the lack of ventilation equipment.The time taken to initiate chest compressions was 36.0 ± 4.1 seconds when 2005-BLS was followed and 15.4 ± 3.0 seconds when 2010-BLS was followed (P < .001). Furthermore, chest compressions were initiated earlier when 2010-BLS was followed (15.4 ± 3.0 seconds) than when 2005-BLS was followed without the performance of rescue breathing (19.8 ± 2.7 seconds; P < .001). The mean time spent on setting up ventilation equipment and performing rescue breathing was 15.9 ± 3.8 seconds, indicating considerable time variations among individuals.Chest compressions were initiated earlier by health care providers who were re-educated according to the 2010 AHA guidelines.