SEATTLE -- A Boeing Co. technician diagnosed with a rare form of terminal leukemia has won a landmark settlement from the aerospace giant after charging he was used as an unwitting guinea pig in tests to determine the medical effect of electromagnetic pulse (EMP) radiation on humans.

Attorneys for the technician, Robert Strom, said the out-of-court agreement announced Wednesday is the first in the nation in which workers have been compensated for their exposure to low-frequency radiation from electromagnetic fields.

Because similar emissions are believed to come from power lines, video display terminals and electric blankets, attorneys said this case could lead to other legal actions.

''The power companies and utilities should now be on notice,'' said Michael Withey, lead attorney in the case, ''that you can't put an electric substation next to a school.''

He said the settlement represents a ''clarion call'' that electromagnetic field exposure can cause cancers in humans and can be used as grounds for health-related lawsuits.

In settling the case on the eve of trial, Boeing refused to acknowledge liability or wrongdoing in respect to Strom's illness. But Boeing agreed to pay Strom $500,000 in cash and annuities. Boeing also said it will change work procedures for its radiation testing employees and would pay for up to 10 medical exams a year for each of the 707 current and former Boeing workers involved in EMP radiation testing.

Attorneys said Boeing has already constructed a new EMP test facility that gives workers radiation protection and had implemented new work procedures advising employees of the potential risks.

''I feel vindicated by this incredible victory,'' said Strom, 50, who said he plans to use some of the settlement money to establish a foundation to publicly expose the dangers of electromagnetic radiation. He still works for Boeing.

The settlement also provides for the creation of a $200,000 fund to pay for a medical administrator who will monitor the health of the affected workers and review the group's prognosis to see whether they have been adversely affected.

A Boeing spokesman said the company was already committed to health screening of its workers to ensure their safety and noted that Strom had lost a worker's compensation case against the company.

Strom maintained he was never told there might be health consequences to his work, which involved sitting in a room in a Boeing complex and shooting EMP radiation pulses into components of MX missiles. But he subsequently was diagnosed as suffering from chronic myelogenous leukemia.

"They never told me that the room I was sitting in was being subjected to radiation, too,'' Strom said.