The Local Authorities (Mayoral Elections) (England and Wales) Regulations 2002

Sealing of ballot boxes

30.  Immediately before the commencement of the poll, the presiding officer shall—

(a) show the ballot box, empty, to such persons, if any, as are present in the polling station, so that they may see that the box is empty;

(b) lock up the box (if it has a lock);

(c) place his seal—

(i) on the lock; or

(ii) where the ballot box has no lock, on the box,

in such a manner as to prevent its being opened without breaking the seal;

(d) place the box in his view for the receipt of ballot papers; and

(e) keep the box locked and sealed or, as the case may be, sealed.