Many American workers with income from more than one source have avoided setting up Keogh plans because they are not aware that they are eligible, pension consultants say.

Under the current law, an individual covered by a government or private company pension plan cannot gain retirement program tax shelters on that salary, but if the individual has earnings from other self-employment, the latter income is eligible for tax deferred status in a Keogh plan.

If the second source of earnings is not from an individual's own business but from work he does for others, the individual may still be eligible.

There are two tests, according to tax experts. The first is the formal Internal Revenue Service test of whether someone is an "independent contractor."

Generally, if a person is his or her on supervisor, with the freedom to set working hours and determine how the particular job is to be done, he or she is considered an independent contractor - or self-employed - for tax purposes.

A simpler test, tax expert E.M. Abramson explained, is whether or not federal withholding and Social Security taxes are taken out of the paycheck.

Persons who work as consultants to companies or institutions or do freelance work without a contract for publications or firms may be eligible to set up Keogh plans even if they have full-time jobs with companies that have pension programs, he said.

"If you are paid the entire sum agreed on without those deductions and you can pass the independent contractor test about freedom in doing your job, you are eligible, most certainly," he said.