Intimate examinations carried out by an ambulance volunteer accused of sexual assaults should only be done in hospital, a court heard.
John Franklin claims ECGs in which bras were removed, vaginal examinations and taking a rectal temperature were "medically required".
But expert Paul Gates, who has trained about 100 paramedics and technicians, said such procedures should never be carried out in "pre-hospital" situations.
Defendant John Franklin outside Maidstone Crown Court
Franklin was an emergency transport attendant with St John Ambulance - the highest qualification - in Sittingbourne, ran a private ambulance company called J R Ambulance Services and was a volunteer on the Urban Blue Bus in Maidstone when he was alleged to have committed the assaults.
"The examination is not taught as part of my own professional practice and it is not part of St John Ambulance training..." - Paul Gates, London Ambulance Service
The 39-year-old married father is also accused of raping and indecently assaulting a pregnant woman several years ago, calling her a "dirty girl".
Maidstone Crown Court was told some of the offences were committed in late 2011 and early 2012 and those concerning the pregnant woman more than 17 years ago.
Prosecutor Anthony Prosser said the former soldier asked a student, aged 18, to let him conduct a medical assessment of her in the back of his private ambulance in Crown Quay Lane, Sittingbourne.
Believing it was part of training for him to become a paramedic, she removed all her clothes and he twice touched her breasts and carried out internal examinations.
"While he did this he called her a dirty girl and tutted," said the prosecutor. "He told her not to tell anyone because it was strange, especially St John Ambulance."
John Franklin denies sexual assault
Mr Gates, deputy director of operations with the London Ambulance Service, told the jury taking a rectal temperature was "clearly inappropriate" and not part of the St John Ambulance syllabus.
A vaginal examination would only be carried out, he said, when a baby was about to be born.
"The examination is not taught as part of my own professional practice and it is not part of St John Ambulance training," said Mr Gates.
To preserve the modesty and dignity of a female patient, an ECG would normally involve placing electrodes on limbs.
"In my 21 years I have never seen a bra that has become a hindrance," said Mr Gates. "In some respects it is helpful to provide support if there is a large amount of tissue."
The case was heard at Maidstone Crown Court
Franklin, of Kent Avenue, Sittingbourne, denies rape, indecent assault, two charges of assault by penetration and three of sexual assault and the historic rape and indecent of a woman.
The trial continues.