Eight of every 10 federal blue-collar workers, including nearly 20,000 here, could have their pay frozen for at least a year under legislation due for debate in the House today.

At issue is the five-step longevity system the government used to compensate its half million mechanics, laborers, carpenters and others under the wage board pay system. The bill before the House would cut Defense blue-collar civilians back to a two-step pay system.

Federal blue-collar workers, whose salaries are pegged to the going rate in local industry, get annual adjustments to bring them in line. In addition, they moved up through five pay steps in each grade, with each step being worth a 4 per cent raise. The fifth, top step, is about 12 per cent more (the government says) that the salary paid by private industry for the same job. Under the longevity system, workers reach the top step after six years in the same job.

Language in the Defense appropriations bill would eliminate the last three longevity steps (worth 12 per cent to employees) for blue-collar Defense aides. The money package does not affect other federal blue-collar workers yet.

If the House approves the two-step Defense pay plan, it would mean that nearly all the 20,000 local Army, Navy, Air Force and Marine blue-collar civilians would be left out of a catch-up with industry raise due this fall. Most are being paid salaries above the second step level, and it would halt longevity raises for them for them for the next nine months or longer if Congress extends the cutoff.

Blue-collar workers outside Defense would still get the catch-up-with-industry raises because they would continue to have a five-step pay system. This would be the case unless Congress decides to trim them back to two steps along lines suggested by the Carter administration.

Some House members are upset with the Apropriations Committee for pushing the longevity pay cutoff on grounds it is part of the legislative turf of the House Post Office-Civil Service Committee. Rep. Gladys Noon Spellman (D-Md.) is holding hearings on the blue-collar pay system, and has been mobilizing support - along with other area legislator - to amend the bill and protect the five-step plan. At least one member of the Appropriations Committee has tentatively agreed to support the Spellman plan on the floor today.

Federal employee unions are worried about the impact on Defense members, and also fear that the longevity pay cutoff could be extended to workers in other agencies.

Millions of dollars in furture raises are at stake in the vote which could come today or Friday.

Who Guards The Guards? Half the Federal Reserve Board's night shift guard force walked off the job Tuesday evening following a dispute over a promotion. Details are unclear, but one guard said the troops were angry because a day-side staffer had been promoted to the bodyguard staff of Fed Chairman Arthur Burns.

When other employees asked why the job hadn't been advertised, the guard says, they were told by a supervisor that it was none of their supervisor that it was none of their affair, or words to that effect. At that point - and this is fact - four of the eight guards scheduled for duty went home.

A board spokesman said it was his understanding that the dispute arose when some guards "misunderstood" their options when they asked the supervisor about the promotion. He said the promotion wasn't to Burns' 4-man personal security staff, but to an investigative job. At any rate, he agrees that four guards went home, but says they returned to work when they were called by another supervisor who "explained" the situation. Everybody is back at work now, and the board is no longer half safe in the evening.

Jerry Rosenthal, Agency for Intertional Development's acting press chief, gets a retirement party send-off this evening at State. The former Milwaukee Sentinel newsman has spend the last 14 years winning a batch of professional wards and producing AID films on three continents.