IT NOW APPEARS likely that the tax reform bill will be one of the first measures to be considered under new Senate rules allowing television coverage of chamber proceedings. For the past 10 weeks floor debate has been broadcast on radio; closed-circuit television has been available only to Senate offices. But on June 1, live TV coverage to the nation will become a reality. C-SPAN, which serves one out of every four American homes with television, is prepared to provide its affiliates with gavel-to-gavel coverage immediately, and commercial networks are expected to use tapes extensively in their news broadcasts.

Television coverage of House debate has been allowed since 1979, and while these programs are no threat to Bill Cosby or even the 6 o'clock news, they have a devoted audience that stays tuned for run-of-the-mill debates and less than critical votes. When the subject is tax breaks, fairness and who pays what, there is likely to be a pretty big audience.

Even without televized debate, it has been no secret that the Senate tends to treat tax bills as Christmas trees, structures to be adorned with special plums for favored industries, hometowns and individuals. Convoluted language has been used to obscure tax breaks that would not have survived public scrutiny. Television won't make this impossible, just harder. With millions of voters watching live debate, the opportunity for mumbled explanations and quick voice votes will be diminished and the chances for comprehensible and fair legislation will grow. Debate on the tax bill is the perfect occasion for television coverage of the Senate to begin.