Gary,
The vendor may indicate to you a set of hex codes to be used to indicate font change. If that is the case, look closely at Chapter 2 paragraph 9 (2.9) for indications of using escaping to transfer special characters.
The vendor will need to support the use of escape (many do not even know the topic is addressed by HL/7).
Jim Kosloskey
email: jim.kosloskey@jim-kosloskey.com 29+ years Cloverleaf, 59 years IT - old fart.