http://www.legislation.gov.uk/ukpga/2000/23/section/26/notesLegislationCrime and law enforcementPoliceCivil and human rightsPrivacy and data protectionExplanatory Notes to Regulation of Investigatory Powers Act 2000Home OfficeKing's Printer of Acts of Parliament2018-08-22 23 28 July 2000 181 This section describes and defines the conduct that can be authorised under this Part of the Act. Three types of activity are covered: "directed surveillance", "intrusive surveillance" and the conduct and use of covert human intelligence sources. 182 "Directed surveillance" is defined in subsection (2) as covert surveillance that is undertaken in relation to a specific investigation or a specific operation which is likely to result in the obtaining of private information about a person (whether or not one specifically identified for the purposes of the investigation or operation); and otherwise than by way of an immediate response to events or circumstances the nature of which is such that it would not be reasonably practicable for an authorisation under this Part to be sought for the carrying out of the surveillance. By subsection (9), surveillance will be covert where it is carried out in a manner calculated to ensure that the person or persons subject to the surveillance are unaware that it is or may be taking place. Directed surveillance may also include the interception of communications where there is no interception warrant and where the communication is sent by or is intended for a person who has consented to the interception (section 48(4)). 183 "Intrusive surveillance" is defined in subsections (3) to (5) as covert surveillance carried out in relation to anything taking place on residential premises or in any private vehicle. This kind of surveillance may take place by means either of a person or device located inside residential premises or a private vehicle of the person who is subject to the surveillance or by means of a device placed outside which consistently provides a product of equivalent quality and detail as a product which would be obtained from a device located inside. 184 For these purposes, a private vehicle is one used primarily for private purposes, for example for family, leisure or domestic purposes (section 48(1)). Subsection (4) provides that surveillance is not intrusive when the device is one that only provides information about the location of the vehicle (eg a tracking device). 185 Subsection (6) provides that surveillance carried out by means of apparatus designed or adapted for the purpose of detecting the installation or use of a television receiver is neither directed nor intrusive. 186 Subsection (8) defines a "covert human intelligence source". 187 Subsection (10) defines "private information", in relation to a person, as including any information relating to his private or family life.