It would take a hearing room the size of Rhode Island to squeeze in all the people who want to see what the House Rules Committee does to them today.

At issue: the mutli-billion-dollar when-and-how-much question involving COL (cost of living) raises for all U.S. retirees, from ex-generals to ex-janitors. Also, waiting in the wings are 260,000 workers who are trying to decide whether to retire or stay on.

What is about to happen is that the committee (the House's legislative traffic cop) will decide how the full House is to decide an important budget resolution later this week.

Of major interest to 100,000 retirees here is what the committee does about the next COL raise. It is a 7.7 percent (before taxes) inflation catch-up due to go into effect next month.

Congress is hellbent, for economy-politics reasons, on cutting out one of the next two COL raises due retirees. The Senate has approved legislation that would have retirees skip the upcoming September boost, and get a full inflation catch-up next March.

The bill before the House Rules Committee would let retirees have the 7.7 percent raise this September. But they would have to skip the March 1981 adjustment.

A sleeper in the House bill is of major concern to the 260,000 people who is eligible to retire right now. It would eliminate two long-standing benefits that allow new retirees to benefit from COL raises that occur before, and after, they retire.

Under current law retirees could quit as late as this Aug. 30 and get benefit of most of the COL raise that went into effect last March, plus all the 7.7 percent due in September.

The House bill would eliminate the "look back" provision, and also prorate the amount of the upcoming raises so that people quitting this month would get only one-sixth of it, rather than the full 7.7 percent.

Some members of Congress think it is dirty pool to change the retirement rules this late in the game. They believe the COL cutback plan can be beaten if the full House is given the opportunity to vote on it as a separate issue, rather than as part of the full budget package.

Opponents of the law which gives U.S. reitrees COL raises every six months say eliminating one of the two raises is an integral part of the budget-cutting operation. They want it voted on as part of the full package going to the House floor this week. The Rules Committee must decide whether the COL can be voted on as a separate amendment, if it must sink or swim as part of the "reconciliation" budget bill.

Rep. Joseph Fisher (D-Va.) wants the House to vote separately on the COL item. He thinks there are enough to votes -- thanks to a strong lobbying by U.S. retiree groups and unions -- to kill the COL cutback. He plans to offer an amendment on the House floor later this week to get the separate vote.

But Fisher won't get the chance unless the Rules Committee today okays an amendment by one of its members, Rep. Robert Baughman (R-Md.), to allow Fisher to make the amendment. The House would then not be forced to vote separately on the COL issue.

If something happens to prevent the Senate and House from coming up with a COL changing bill by Sept. 1, retirees will get the full 7.7 percent raise. And people planning to retire this month can do so and still take advantage of the "look back" as well as qualifying for the full 7.7 percent raise.