what is the scope of accept-range

(this is a minor point)

In section 14.5:                                                                       
    The Accept-Ranges response-header field allows the server to
    indicate   its acceptance of range requests for a resource ....              
     Origin servers that accept byte-range requests MAY send 
     Accept-Ranges: bytes                                                  

It's a bit unclear what the scope of the accept-range
response header is. Is it just for the requested resources, or for a larger
set of resources?

That is, if the origin server will accept byte-range requests
for some, but not all, resources (say, not for html documents with
server side includes),  then what is the proper usage of
Accept-Ranges:?