Once you become certified as a nursing assistant your name is listed on the California Nurse Aide Registry. The listing is kept on the registry for twenty-four months. To renew your certification for another twenty-four months and maintain an active status on the registry, you need to work for at least eight hours within those two years. In addition, you must attend forty-eight hours of in-service education. Renewal notices are sent to each nurse aide four months prior to the certification expiration date.