Direction to certain aerodrome managers under the Aviation Security Act 1982 relating to security scanners 2015, annex C, section 14

14. An individual who has been selected to be screened by security scanner may opt out of being scanned but only if the individual being screened agrees to be searched by an alternative screening method, including at least an enhanced hand search in private. That search may require the loosening or removal of clothing.

Alternatives
An individual may opt out of being scanned. In this instance, the individual must either be screened by an alternative method which includes at least an enhanced hand search in private or that individual must not be permitted to enter the security restricted area, or, if applicable, he or she must be removed from it. An enhanced hand search in private must take place in a private room or an area away from the main search comb. This may involve the loosening or removal of clothing.

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20. In the event that an individual declines to be scanned and refuses to undergo the alternative screening method of at least an enhanced hand search in private, the incident shall be escalated to the appropriate member of security staff who will escort that passenger landside and advise the passenger’s airline that they have been refused access to the security restricted area and that the passenger should be offloaded. In the instance of suspicious circumstances local processes for dealing with suspicious individuals should be followed.