W-2 Name Character Limit

PeopleSoft 9.2, PT 8.59.22, PUM 47

What is the character limit for the employee name in Form W-2? I received a question from an employee who does not have a first name and has two separate last names. The first name on the Social Security card is FNU. The employee's full name is only 16 characters, including all spaces. For the W-2, the first name is showing with only the first character of F. It seems like there's plenty of room to include the full first name of FNU along with the two last names. Since the first name is showing