After a management retreat with 25 staffers at a suburban Baltimore Marriott hotel, Labor Secretary William E. Brock outlined a plan yesterday to improve the efficiency of agencies criticized by the General Accounting Office and Brock's own staff.

A GAO study had said the Labor Department "lacks credibility" in key areas for not policing the nation's $900 billion pension and health insurance system more effectively and for delays in issuing health and safety rules to protect workers.

Each agency head has 60 days to produce a list of major goals and "milestones" by which Brock can measure performance. Undersecretary Dennis Whitfield will ride herd.

Improved auditing of programs such as the $15 billion unemployment compensation system and the $2 billion Job Training Partnership Act are top priorities, along with attempts to speed up and improve rule-making by two of the most widely criticized agencies, the Occupational Safety and Health Administration and Mine Safety and Health Administration.

The new plan also formally lays out Brock's three major goals for the department:

*"To improve the economic opportunity of American workers through emphasis on job opportunities, health and safety and retirement security.

*"To increase the ability of Americans to compete successfully in domestic and world markets through labor-management cooperation, education and training, retraining, and cost-effective federal regulations.

*"To improve productivity, effectiveness and creativity of DOL operations through employe motivation and involvement, intradepartmental coordination, and private-sector support."

Inside the department, there are fears that the reference to "private-sector support" may mean increased contracting-out of department functions -- including processing of health claims for black lung ailments -- and various OSHA activities.

Deputy Secretary David Demarest said that while the new management plan does not change policy here, some data-processing has been contracted to private firms, "and we always review the process by which we provide various services, and try to find the most efficient way to fund them."

While labor unions may welcome some of Brock's changes, the department's choice of the Hunt Valley Marriott for its overnight retreat two weeks ago may ruffle a few feathers. The nonunion Marriott chain has been picketed in various cities for alleged antiunion policies that have prevented organizing.

INTO THE FRAY . . . Incoming OSHA chief John A. Pendergrass, an industrial hygienist for the Minnesota Mining and Manufacturing Co., will have his hands full fighting off persistent criticism.

The latest flap involves a threat by the Office of Management and Budget to delay a new OSHA regulation aimed at protecting textile workers from byssinosis, or brown lung disease.

The controversy, first reported in The New York Times, involves OMB's concern about increased costs for companies required to provide medical examinations to workers who might be exposed to dangerous cotton dust. The standard was agreed to by industry and union officials, but the OMB believes the costs may be too burdensome. An OSHA estimate says early surveillance could help prevent up to 6,000 workers from contracting the disease.