I am interested in using AI processing of data, e.g. audio transcription, but I don't want that data to be used further as it needs to remain confidential. I don't want it to be stored or analyzed beyond my needs.

It's not clear from reading any privacy policies if any companies provide this service or and explicitly state that they will never use data for unintended purposes.

Is there some standard that certifies this type of data privacy? I'm an individual user. It seems anything that has any degree of confidentiality is marketed for business.