They have no right to search you. They can request and presumably most people agree in order to be allowed access airside. The same principle with searching your bags. They need to ask permission. As for touching you 'intimately' I have posted the following previously...
From the Sexual Offences Act 2003
>>>3 Sexual assault
(1) A person (A) commits an offence if-
(a) he intentionally touches another person (B),
(b) the touching is sexual,
(c) B does not consent to the touching, and
(d) A does not reasonably believe that B consents.
(2) Whether a belief is reasonable is to be determined having regard to all the circumstances, including any steps A has taken to ascertain whether B consents.
(3) Sections 75 and 76 apply to an offence under this section.
(4) A person guilty of an offence under this section is liable-
(a) on summary conviction, to imprisonment for a term not exceeding 6 months or a fine not exceeding the statutory maximum or both;
(b) on conviction on indictment, to imprisonment for a term not exceeding 10 years. <<<
As far as I am concerned if I give a permission to a security person to physically search me I am not reasonably expecting that search to include a search of my genitals. If that person is doing it delibrately and not accidently then it must be sexually motivated. If it happens to me I am calling the police. It may be difficult to prove and may go nowhere but that is not my problem. My duty is to report the crime.