The City Council passed a resolution ordering City Manager Robert W. Healy to investigate the Somerville laundry business that cleans all of Cambridge Hospital's patient linens last night.

A group of mostly minority laundry workers seeking to unionize has been battling Royal Institutional Services Inc.

Royal has a three-year, $214,000 contract with the city to do the hospital's laundry, according to Marka Peterson, an organizer of the Union of Needletrades Industrial and Textile Employees (UNITE). UNITE claims that the 150 workers, most of whom receive between 54.50 and 56 per hour, are underpaid and subjected to dangerous work conditions, including exposure to blood and feces. They also charged that Royal has offered an unreasonably expensive health-insurance plan for its employees.

"I work there all the time with all the blood that comes with the laundry," said Hector Lones, a Royal janitor. "It's not enough-the salary they're giving me."

But Royal's president, Mark Johnson, has contended that UNITE's and the workers' actions are part of an intimidation campaign against non-union firms. He has denied the allegations of safety violations.

The National labor Relations Board has ruled that Royal had unfairly fired two employees. In addition, Royal is under investigation by the federal Occupational Safety and Health Administration. And workers have filed complaints with the state Attorney General's office and the state Commission Against Discrimination. The council unanimously approved a resolution demanding that the city manager look into Royal and that Cambridge Hospital review its contracting policies.

"Before we privatize services we should make sure that businesses meet fair labor standards," said Councillor said Kathleen I. Born.

But Healy said the city cannot do much unless federal or state agencies find that Royal broke laws. The city has no investigatory agency of its own, and usually only investigates construction companies, not service firms, before subcontracting, Healy said. Generally, a contract can only be terminated if a clear breach of the contract occurs.