THE LINE WAITING outside the Senate for the debate on the Federal Trade Commission's routine authorization bill is awesome. It is not made up primarily of bureaucrats worried about their jobs, as such lines sometimes are. Or, even, of the commissioners of this embattled agency. Instead, it includes people from the insurance industry, used-car dealers, breakfast-cereal makers, growers of oranges, funeral directors, the manufacturer of Formica, builders of "mobile homes," professionals like doctors and lawyers, and the makes of antacids.

They (and others) are lined up with one simple hope.

They want the Senate to outlaw existing or proposed FTC actions that interfere with tidy (and highly profitable) business arrangements. You will note that the waiting line does not include average citizens. They are not there because nothing in this bill would help them, although many of its provisions would hurt them.

The insurance industry, for instance, wants Congress to tell the FTC never to investigate it. Why? The FTC, which can now investigate but not regulate that industry, reported not long ago that the buyers of life insurance paid $1.3 billion in excess premiums during one year. The industry didn't like that.

The growers of oranges, to take another group, want Congress to stop in its tracks an antitrust case aimed at Sunkist. The funeral directors want Congress to remove the threat that they may be required to give customers an itemized price list. The "mobile home" makers don't want the FTC to require them to live up to the warranties they give. The list goes on. And on.

In other words, what started life last year as a proposal to put in an authorization bill language to curb the worst abuses of the FTC has become a Christmas tree for a wealth of interest groups. Almost every industry that has run afoul of the FTC in recent years has taken its plea for relief to Capitol Hill and found a sympathetic ear. In the trading that has gone on, one after another of these pleas has made its way either into the bill reported by the Commerce Committee or into amendments to be offered on the Senate floor. The result is an assault on the knowledge available to consumers -- not to mention the attack on their pocketbooks -- that puts to shame even the water projects bill passed yesterday by the House.

The FTC is far from being perfect. It deserves some of the cuffing around it is getting on Capitol Hill this year, but it has done nothing to justify this kind of assault.

If the Senate has any sense of what government regulation should be and of what kind of protections the average citizen needs from predatory business practices, it will strip from this bill every single effort to roll back or cut off or bar FTC investigations and regulations. It is too late now to try to figure out which, if any, of these rollbacks, cutoffs and bars has any legitimate justification, and throwing them out would still leave the Senate with more than enough serious proposals aimed at changing the FTC's practices. It would also leave the average citizen with some of the protections he needs but is now, suddenly, in danger of losing.