A "press conference" held by Harvard personnel officers yesterday turned at times into a shouting match between the administrators and some 50 students who came to protest one of the University's employment practices.

The students demanded a change in Harvard's system of dividing its painting crews into "painters helpers" and "journeyman painters." The helpers get from 43c to 86c less per hour than the journeymen because-according to the University-they are still learning the skills of the trade.

About 75 SDS members voted last night to stage a non-obstructive sit-in in Dean May's office today in support of the workers demands and another demand that the Cambridge Project be stopped.

The sit-in, which will follow a 1 p.m. rally outside University Hall, will last until 5 p.m. when, SDS members said, they will decide whether to stay through the night.

But the students-repeating arguments made in SDS statements early in the week-accused Harvard of "racism" and "oppression of black and white workers" in its treatment of the helpers. Specifically, they charged that:

Harvard makes the helpers do exactly the same work as the better-paid journeymen;

qualified black workers have been hired as helpers instead of journeymen, even though they had several years' experience as painters. Seven of the 12 helpers are black, and three of 27 journeymen are black.

The University representatives-including John B. Butler, director of personnel; L. Gard Wiggins. administrative vice president; Dean May and Edward W. Powers. Harvard's labor-relations manager-replied several times that helpers do not have the same qualifications as journeymen.

"There are a large variety of tasks andskills in painting, and the idea is to expose the helper to all the tasks and let him become proficient," one of the officials explained.

"Helpers are training other helpers; often they are working alone," Jared Israel '67 yelled back from the crowd. Throughout the ninety-minute meeting other students said that helpers spend nearly all their time doing the same routine painting jobs as journeymen.

"Why does a black man with five years' experience as a painter need more training as a helper?" one student asked. "How do you decide who is 'qualified'?"

"We depend on our foremen to check qualifications," William Murphy, director of Buildings and Grounds, answered. He said that twice in the last year Harvard has hired black workers directly as journeymen without making them spend time as helpers.

But after a series of questions about specific cases, where-the students claimed-workers with long experience were made helpers, the administrators said they were not familiar with details of each case. "Where's the foreman?" students asked. "Why isn't he here?"

Butler and Powers said that Harvard is now reviewing the whole system of job classification with the union that represents the painters.

In answering several questions. Powers emphasized union rules. He said that any worker who felt he had been misclassify could go through a regular grievance procedure.

"Black workers have no one in the union they can rely on." Diorite C. Fletcher '71 said. "That is why some of us who are black are here. Black painters have to be careful because they need their jobs and can't trust their foreman or union officials to represent them."

The argument became more heated when Larry Kinnard, a black personnel officer hired this fall, came into the room. He cut off several white questioners-saying "let me talk to the sister"-and said that his job was to "watch out for black people" in the personnel office.

After several minutes of talking. Claire Joseph '71 asked Kinnard. "Will you join us? Will you demand right now that the painters' helpers get the same pay as the painters?"

"I can't move on a problem until someone comes to me and talks about it." Kinnard said. "Why don't you come to me and we'll talk about it."

Miss Fletcher then moved around Kinnard and confronted Butler. "I want to single you out for the most insidious, most racist, most history-repeating performance I've ever seen," she said. "You take a black brother-one with five babies-and you bring him in here and pull the fucking strings and don't let him say what he wants."

Kinnard left the main room and spoke with several black students in the hall. After a few more exchanges the administrators stood up and left.