Safe custody of all return envelopes, etc.
30.—(1)  Subject to paragraph (2), all papers that are or purport to be return envelopes containing the postal ballot papers for an election received by the Returning Officer —
(a)must be kept in safe custody and remain sealed; and
(b)must not be opened or tampered with before the pre‑count examination of postal voting papers under section 56C of the Act.
(2)  If the Returning Officer has reasonable grounds to believe that a return envelope contains harmful or hazardous substances, the Returning Officer must —
(a)open the return envelope for the purposes of examining the existence of the harmful or hazardous substances;
(b)record the result of the examination; and
(c)inform the following persons as soon as possible of the result:
(i)in the case of a general election and —
(A)if the Returning Officer is able to determine the electoral division to which the return envelope relates — the candidates in a contested election for the electoral division or their election agents;
(B)if sub‑paragraph (A) does not apply — all candidates in a contested election at the general election or their election agents;
(ii)in the case of a by‑election — all candidates in the by‑election or their election agents.
(3)  If a return envelope is opened in accordance with paragraph (2), any postal ballot paper contained in that return envelope must not be accepted for counting, regardless of the result of the examination.
(4)  If the return envelope contains harmful or hazardous substances, the return envelope (and any postal ballot paper inside) must be disposed of in a safe manner and in a manner that does not compromise voter secrecy.
(5)  If the return envelope does not contain harmful or hazardous substances, the return envelope (and any postal ballot paper inside) must be dealt with in the manner set out in section 56E(2) of the Act.