Facsimile machines, those beeping little devices increasingly used to send everything from office memos to Valentine greetings, are sparking demands for laws against "fax attacks."

Washington is one of at least eight states considering proposals to curb what critics say is a rising tide of "junk fax" - printed advertisements that pop up unsolicited on office and home fax machines.Fax owners and dealers told a legislative panel here recently that the machines, which owners tend to leave hooked up to phone lines 24 hours a day, are completely vulnerable to "fax attacks" of unwanted advertisements.

Transmissions, which take an average of a minute per page, can tie up a machine and prevent the sending or receiving of desired documents, said Lee Bowman, a facsimile machine salesman who supports regulation. The receiver also has to pay for the paper the incoming advertisement is printed on, whether it's wanted or not.

"This is the ultimate in abusive use of a private communication system," complained Rep. Ken Jacobsen, a Democrat from Seattle who is sponsoring a measure to restrict junk fax transmissions. "You get a message you didn't want from people you don't know on paper they didn't buy."

His researcher, Deborah Senn, said other states considering similar legislation are Connecticut, Oregon, California, Michigan, Minnesota, New York and Maryland. About 2 million of the devices have been sold in the United States in the last few years, she said, and their popularity is growing.

The junk fax problem seems to be on the verge of exploding, Jacobsen said.

But Bill McCue, president of Public FAX, an Orange, Calif., publisher of a fax directory and trade magazine, contends the problem is largely a creation of news organizations. Because public relations people like to send releases by fax, he said, the media appear to be the one group that does suffer an inundation of junk fax.

For everyone else, he said, the media are "making a monumental problem out of nothing. It's a cheap shot. It really is."

Donna Murdoch, executive director of the American Facsimile Association in Philadelphia, agreed.

"We ask people, `How many pieces of junk fax are you really getting?"' she said. "And people say the most they can remember getting is two pieces in a week."

But Jacobsen asserted that if junk fax is not a major problem now, it soon will be. He noted that one computer maker already is marketing a device that can dial randomly and automatically send advertisements when a connection to a fax machine is made.

Jacobsen's measure, which is expected to clear the House soon and head for the Senate, would require senders of commercial solicitations to get advance permission from the intended receiver. Violators could face civil action that could net the unwilling recipient of the junk fax up to $500.

McCue called the proposal, which is similar to legislation being considered in Oregon and Connecticut, "lunacy." But Bowman said he and colleagues think it's reasonable.

Bowman said the junk problem "is only going to grow here, just as it already has in Japan," where fax machines are so popular that coin-operated units can be found in restaurants and hotels.

He told the House committee that junk fax advertisers are offering prizes in exchange for the telephone numbers of fax machines. "The numbers are worth money to these people," he said. "In the next five or 10 years, junk fax could get real bad, especially once fax machines start getting into households."