I have a type O non-immigrant visa and need to apply for a work permit. I was told by the head of the department that I must go to my embassy and obtain a letter certifying my degree. I have never heard of this regulation. Can someone please tell me if this is the regulation and if not, what is the procaess for obtaining a work permit in a government secondary school.

This may well be the case.

When I came to work in Thailand 20+ years ago I had to get all my educational documents certified by a Notary Public in the UK,

to assist with my work permit application when I arrived.

I was not working in education, but it seemed to be a general rule for all.