After their first election last June the nurses at Prince William Hospital thought they had a union.

By a count of 66-34, they did.

But hospital administrators challenged the electoral procedures, and the decision to unionize the nurses was set aside.

When the nurses won a second election in August -- by a vote of 63-44 -- they were positive they were official members of the Prince William Healthcare Professionals Local 724, a unit of the Service Employes International Union AFL-CIO.

But the hospital administration, which had publicly promised to abide by the results of the second ballot, challenged that election, too.

"We just don't want a union here," says E.L. Derring, the chief hospital administrator.

Nurses say they are confused. On one hand, they claim to be members of a union. But they admit they have no contract, no power to negotiate and no recognition from the hospital.

"We . . . have a union," Wendy Baulmer, a nurse at Prince William and one of the union organizers, says uncertainly. "We've held two elections, and won them both. We have an organizing committee and a good chain of communication. . . ."

The issue is now before the National Labor Relations Board, which is expected to decide whether to certify the union. The board could overturn the results of the last election and force nurses to try for another ballot-box victory. If certification is approved, Prince William would be the first hospital in Virginia to have a nursing union.

The battle between the hospital administrators, who insist the nurses' concerns would be best addressed through internal procedures, and the nurses, who say working conditions will never improve unless a union is established, has escalated.

Beginning last summer, the hospital sent numerous letters and pamphlets to nurses' homes, warning of dangers of joining a union. The literature talked about "union bosses," outsiders," loss of freedom" and dreaded "strikes."

The nurses call that a "scare campaign" and, by contrast, say they limit their pro-union efforts to calling other nurses after work and telling them the advantages of organizing. In an effort to inform the public about their fight for a union, the nurses have begun blood-pressure clinics at Manassas shopping centers where they display the union logo and tell shoppers nurses' grievances.

When asked about the events that led to the decision to unionize, nurses said it wasn't so much the low wages or long hours, or the weekends and holidays they are expected to work. It wasn't even the floors they sometimes mop or the bedpans they empty.

"That's all part of the job. We knew that when we went into nursing," says operating room nurse Pat Peer.

What really angers the nurses is staff shortages.

They say it is not unusual for a floor of 44 patients, including several "total care" patients who need intensive services, to be cared for by two registered nurses, two practical nurses and two aides on a single shift.

Of those six employes, only two -- the registered nurses -- are allowed to administer intraveneous feedings, dispense medicines and interpret symptoms of patients.

"It's awful," says Connie Hipple, an RN at Prince William. "We all went into nursing because we wanted to care for sick people. We were very idealistic. It's an awful feeling at the end of the day when you realize you have given just the minimal care to each patient."

"We would never have formed a union just over wages," Hipple adds.

Since the nurses began their move to organize, tensions have mounted and both sides in the dispute have leveled serious legal charges at each other.

The hospital claims the union failed to post proper notice of the August election and thereby invalidated the second election results.

On the other hand, the nurses claim the hospital engaged in unfair labor practices by withholding annual raises since last May during the union organizing drive. (The National Labor Relations Board is expected to issue a complaint against the hospital on that charge later this week).

And the nurses charge that the hospital is using the oldest trick in the union-busting book: Delay, delay, delay, until people get fed up with the fight and union support erodes.

"But we're gaining strength," asserts Tina Gordon, a critical-care nurse who believes the hospital tactics are backfiring. "A lot of the girls see what the administration is doing and it's making them mad.

"I've seen several anti-union people change their minds during the past month."

While both parties wait for decisions by the National Labor Relations Board on their separate allegations, they admit the atmosphere at Prince William Hospital is becoming increasingly bitter.

The active pro-unions nurses say they are experiencing subtle forms of harassment as work and have been told that their efforts to form the first nurses' union in the state has effectively blackballed them in the Virginia nursing profession.

"We know we will never be able to work as nurses anywhere else in the state of Virginia," says Hipple. ". . . Most of us who are active want to stay at Prince William. . . ."

An area hospital administrator, who asked not to be identified, agreed. "Let's just say there is quite a network out there," the administrator said. "But they would have a hard time proving they've been blackballed. . . ."

The hospital administration concedes it fears a union within its walls and has vowed to use all legal means to prevent the establishment of one.

"I don't want the threat of a work stoppage at a health care facility," says Derring flatly.

But the nurses say they are tired of hospital administrators, almost exclusively men, deciding what is best for them.

"The nurses really run the hospitals," says one nurse. "We're there eight hours a day and the doctors might stop in on a patient for five minutes, but we have no input into the decisions that are made that affect us.

"But more than that, I think the idea of women organizing frightens men."