Federal workers threatened with pay and grade cuts because of reclassification or reorganization shakeups would get money and status protection under a legislative plan that has the personal blessing of President Carter.

Administration officials outlined the no-fault downgrading proposal yesterday to the House Compensation and Employees Benefits subcommittee. Civil Service Chairman Alan K. Campbell told subcommittee chairwoman Glayds N. Spellman (D-Md.) that a bill providing the pay and grade savings would be submitted soon.

Downgrading is much on the minds of the nearly 2 million white and bluecollar federal workers because of tough new job classification audits, and shake-ups that will be caused by White House reorganizations of agencies and missions.

Several bills are pending before Congress to provide grade and pay protection for workers hit by downgradings resulting from classification audits that find jobs that are rated too high and are paid too much.

Rep. Robert N. C. Nix (D-Pa.) has proposed lifetime pay and grade retention for those workers for as long as they remain in the same jobs. His bill also would extend the protection to downgradings that have taken place within the last two years.

The Nix bill - he's chairman of the Post Office-Civil Service Committee - does not cover downgradings resulting from reorganizations or reductions in force. Six of every 10 downgrading action in government now result from either a reorganization or a RIF. With Carter's plans to shake up the bureaucracy and repackable and streamline it, more downgradings are in the works.

Purpose of the White House plans is threefold:

1) To give protection to employees whose jobs are (as, they say in government) "adversely impacted" by either a desk audit demotion, or a reorganization or layoff-related demotion.

2) To "protect the integrity" of the federal job classification system by granting grade retention rights for a limited time, rather than for life, as would be the case under the Nix bill.

3) To insure federal workers that reorganizations won't wreck their careers, and thereby minimize bureaucratic resistance and foot-dragging in reorganization actions.

As outlined by Campbell, this is the administration proposal that - if it is okayed by Congress - would permit Carter to keep his promise to government workers that "nobody" would be hurt, lose a job or lose money because of reorganization. Here it is:

A pledge that the "downgraded" employee would keep his or her grade for two years.

Indefinite salary retention at the old, or higher grade rate even after the job of the incumbent had been downgraded.

Future pay raises that would be 50 per cent of the regular percentage increase given to other federal workers. (Under this, employees who had been downgraded would eventually reach the salary of their new, lower grade.)

The two-year grade saving plan and the indefinite pay retention plan would apply to all demotions. This would include not only downgradings resulting from faulty job classifications, but also downgradings resulting from reduction-in-force actions taken because of reorganization, or for any other RIF.

Most government workers hit by demotion are affected by reorganizations or reductions in force. Adding the save-grade, save-pay featore, insiders say, is the result of arguments by the Office of Management and Budget. The earlier plan proposed to the President would have given job and pay protection only to employees hit by classification actions.

It would also grant the Civil Service Commission extraordinary authority to force, in effect, placements by requiring agencies to take employees whose jobs and grades are in jeopardy because of some classification or RIF action and place them in other position may be even in other agencies - at their current grades and salaries.

Employees who took advantage of the grade and salary retention guarantees would give up certain existing appeal rights. Some members of Congress don't like that at all, but administration insiders say the elimination of "red tape" appeals procedures for employees is a fair trade-off for a grade and pay protection plan that they believe is "on the high side of generosity."