In the summer of 2011, the Commission members changed the work hours required to be eligible to take the CNN exam and in the work hours required for recertification for the CDN and CNN exams. As of 08-01-2012, the work hours required to be eligible to take the CNN exam have been increased to a minimum of 3000 hours working as a nephrology nurse during the three (3) years prior to submission of the exam application. Beginning 08-01-2014, to recertify for the CDN or CNN exam, the required work hours have been increased to a minimum of 1500 hours working in nephrology nursing during the three (3) year certification period. All required work hours must be in nephrology nursing, and the 50% requirement will be eliminated.