§ 211-a. Continuation of salaries of employees of the department while receiving training. The commissioner may, within the amounts appropriated therefor, continue the salaries, in full or in part, of employees of the department and the institutions in the department while such employees are absent from their regular duties and are receiving training for the better performance of duties, provided that no such compensation shall be so continued to a greater extent than will reimburse such employees for the loss of earnings while receiving such training.