Proposed pension changes for current workers would be capped and new hires pensions could be reduced by 80 percent.
Police and firefighters turned out in force in Harrisburg to urge legislators to vote down proposed changes in the state municipal pension laws.
About 500 protesters staged a raucous rally in the Capitol Rotunda on Tuesday, contending that changes approved by the Senate would destroy collective bargaining for employees of local governments.
The president of the Philadelphia firefighters union, Bill Gault, said lawmakers ought to pass a long-delayed state budget before they make changes that affect firefighters' money.
The bill pending in the House would freeze, but not reduce, benefits for current employees covered by pension funds with serious financial problems.
For a small number of funds in the worst shape, including Pittsburgh's, the bill would require a state takeover and allow benefit reductions for future employees.