Official Secrets Act 1911/1920 s3 Definition of prohibited place.

For the purposes of this Act, the expression "prohibited place" means-
 (a)any work of defence, arsenal, naval or air force establishment or station, factory, dockyard, mine, minefield, camp, ship, or aircraft belonging to or occupied by or on behalf of His Majesty, or any telegraph, telephone, wireless or signal station, or office so belonging or occupied, and any place belonging to or occupied by or on behalf of His Majesty and used for the purpose of building, repairing, making, or storing any munitions of war, or any sketches, plans, models or documents relating thereto, or for the purpose of getting any metals, oil, or minerals of use in time of war;
 (b)any place not belonging to His Majesty where any munitions of war, or any sketches, models, plans or documents relating thereto, are being made, repaired, gotten, or stored under contract with, or with any person on behalf of, His Majesty, or otherwise on behalf of His Majesty; and
 (c)any place belonging to or used for the purposes of His Majesty which is for the time being declared by order of a Secretary of State to be a prohibited place for the purposes of this section on the ground that information with respect thereto, or damage thereto, would by useful to an enemy; and
 (d)any railway, road, way, or channel, or other means of communication by land or water (including any works or structures being part thereof or connected therewith), or any place used for gas, water, or electricity works or other works for purposes of a public character, or any place where any munitions of war, or any sketches, models, plans or documents relating thereto, are being made, repaired, or stored otherwise than on behalf of His Majesty, which is for the time being declared by order of a Secretary of State to be a prohibited place for the purposes of this section, on the ground that information with respect thereto, or the destruction or obstruction thereof, or interference therewith, would be useful to an enemy.

Annotations:
Amendments (Textual)
3(a) substituted by Official Secrets Act 1920 (c. 75), Sch. 1
Words substituted by Official Secrets Act 1920 (c. 75), Sch. 1
Words inserted by Official Secrets Act 1920 (c. 75), Sch. 1

Modifications etc. (not altering text)
C1S. 3(c) extended by Civil Aviation Act 1982 (c. 16, SIF 9), s. 18(2)
C2S. 3(c) extended by Atomic Energy Authority Act 1954 (c. 32), s. 6(3), Nuclear Installations Act 1965 (c. 57), Sch. 1 para. 3