American heart association CPR compressions ratio?

1960 Cardiopulmonary resuscitation (CPR) was developed. The American Heart Association started a program to acquaint physicians with close-chest cardiac resuscitation and became the forerunner of CPR training for the general public. 1963 Cardiologist Leonard Scherlis started the American Heart Association's CPR Committee, and the same year, the American Heart Association formally endorsed CPR.

1966 The National Research Council of the National Academy of Sciences convened an ad hoc conference on cardiopulmonary resuscitation. The conference was the direct result of requests from the American National Red Cross and other agencies to establish standardized training and performance standards for CPR.1972 Leonard Cobb held the world's first mass citizen training in CPR in Seattle, Washington called Medic 2. He helped train over 100,000 people the first two years of the programs.