To specify a default element to use for unmapped character formats:
[DITAOptions] ; DefCharElem = element for char formats that are not ; mapped in [DITACharTags], default is "ph" DefCharElem = ph
If your configuration file does not include a value for DefCharElem, DITA2Go uses one of the following as the element for an unmapped format: if UseFormatAsTag=Yes and the format name (adjusted as for CSS class names) matches the name of a valid element in the current content model, the format is mapped to that element; otherwise, the format is mapped to ph, the default value of DefCharElem. See §24.4.2 Treating format names as DITA element names.