Section 21. Service orders

An order made under the provisions of this Act shall-

(a) in the case of an order of general nature or affecting a class of persons be notified in the Gazette; and

(b) in the case of an order directed to a specified individual be served on such individual-

(i) by post under postal certificate or by delivering or tendering it to that individual; or

(ii) if it cannot be so delivered or tendered, by affixing it on the outer door or some other conspicuous part of the premises in which that individual lives and by preparing a return thereof witnessed by two persons living in that locality.