In the U.S., at least on the East Coast, the phrase turn off to mean to cause someone to lose interest, or more strongly, to repel, does not necessarily have a sexual connotation. Where does the phrase mean to have a sexual affinity? Are your uses harmless?

I don’t anticipate using turn off causing hilarity in a formal setting. But there is room for hijinks in a lighter atmosphere.

Is the word sexy? How is the response with a message felt, so if you’re in doubt about what you would like

received, that might be the better expression.

What is sound as an adjective, modifying engineering principles? In this sense, usually considered its second sense, sound means something like strong, secure, or reliable; or competent; or in good condition.

Is engineering principles reliable and safe, probably?