10. The Director may authorise destruction of any specified classes of public records which-(a) by reason of their number, kind or routine nature do not, in his opinion, possess any enduring value for preservation as public archives, and(b) are not required for reference purposes in any public office after action on them is completed or after expiration of such period of years from the date on which action on them is completed as may be agreed upon between the Director and the administrative head of that public office.