How does one decide which "films" need to be certified by the CBFC? Would a long special episode created only for television, with no theratrical release, require certification because it is called a "movie"?. Is a film defined in terms of its length or the format in which it has been released?
If you mean documentaries, when you say Long TV serials and programs (that is what I can think of, by long programs), then officially, they need to be sent to CBFC for review. I am not sure, whether CBFC actually awards a certification for the same. Reason being, if a certification is given, then it has to be displayed before start of the film/feature/ad/documentary.
As per the details present in the FAQ section on CBFC site, for normal TV serials/programs:
Is there CBFC certification for TV?
There is no CBFC certification for T.V programs and serials. However, under Cable Television Network (Regulation) Act, 1995 content code / Advertisement code have been prescribed for programme and advertisements appearing in cable TV Network. The offences under Cable Television Network Regulation Act being non-cognizable, a specific complaint has to be made by an Officer authorised by the State Governments.
However, TV exhibition of a feature film, comes under purview of CBFC certification, and a film must be certified, before it is shown on TV
Will it be illegal to screen uncertified films on the Cable TV?
Yes. Only certified films should be shown on the Cable TV.