Prince William County supervisors did not choke on their dessert when the School Board requested $16 million for teacher and employes salaries -- up $10 million from the amount it sought in September -- at a recent dinner work session. But the supervisors did not make a commitment, either.

The boards met to discuss a study released in the fall showing that county teachers' salaries ranked ninth in a survey of 10 comparable jurisdictions. Instead of a commitment, the Board of Supervisors scheduled another work session, to take place after the legislature releases its school budget sometime in March, to determine what help can be expected from the state.

In addition, the two boards asked County Executive Robert Noe to come back to them with the figure that the county collected in property and personal taxes in 1984. In the 1985 school budget of more than $131.5 million, nearly $51 million came from the state.

School Superintendent Richard Johnson said he expects the state figure to be higher this year. Last year's local funding came to more than $62 million, and more than $3 million came from the federal government.

Although a survey of 500 families last spring revealed that 72 percent of the respondents would be willing to pay higher taxes to support a teacher pay raise, the supervisors were cool to the idea.

"I know if I took a survey of my own constituency, nobody would support higher taxes," Brentsville Supervisor Joseph Reading said later. A real estate tax increase to pay for a $16 million salary raise comes to 32 cents per $100 of assessed value. "This is one-seventh of the board that won't be there" for a tax increase, Reading said, referring to himself.

According to Johnson, the higher figure was requested because "we were trying to show total funding for 10 percent raises for 2,100 teachers and nearly 1,300 school employes, plus step increases the amount that teacher pay goes up annually based on seniority and a cost-of-living raise."

Johnson said the supervisors acknowledged the importance of a pay raise in keeping teachers in the county. Last year 281 teachers left the school system, the largest number to leave since the 1980-81 school year, when 271 quit.

He is hopeful that an agreement to fund the request will be reached, Johnson said. The School Board is required to submit its budget to the supervisors by April.

The recommended salary raise would boost a starting teacher's pay from $14,280 to $16,000.