The Montgomery County Council approved fundamental changes to the county’s troubled disability retirement program Tuesday, creating a two-tiered system that distinguishes incapacitated workers from those who can find a job doing something else.

The new rules also forbid employees who are about to get fired for misconduct from receiving a service-connected disability package.

The changes come nearly three years after the county’s inspector general called attention to the large number of Montgomery police officers who retire on disability. Officers who received the packages had to show only that one injury affected their performance — a bad shoulder, for example — to receive the same benefits as one who was paralyzed on the job.

“I think it was high time they did this,” said Joan Fidler, president of the Montgomery County Taxpayers League.

The legislation passed 7 to 1 with one abstention. Council member George L. Leventhal (D-At Large) voted no; Marc Elrich (D-At Large) abstained.

Leventhal said the county charter calls for changes in benefits to be decided during bargaining between the county and employee unions. “There’s been a breakdown in collective bargaining,” he said, citing labor tensions. “But the remedy isn’t to abandon collective bargaining.”

The new rules go into effect July 1, 2012. Although criticism of Montgomery’s disability system has focused on police officers, the new rules apply to all county employees. Firefighters already have a two-tiered disability system: Those with total incapacity receive at least 70 percent of final earnings. while those with partial incapacity get at least 52.5 percent.

The new rules adopt that same 70/52.5 percent split, a slight boost for the most severely injured. Currently, there is just one rate: 66.7 percent.

Over the past eight years, according to Montgomery officials, 226 public safety employees retired on service-connected disability, representing 77 percent of such county employee retirements. Over the same period, public-safety employees represented considerably lower percentages of service-connected disability retirements in Prince George’s, Howard, Anne Arundel and Fairfax counties, officials said.

With the new rules a year away, more officers could apply. “I expect a spike in claims as employees try to get in under the old system,” said council member Phil Andrews (D-Gaithersburg-Rockville).

County Executive Isiah Leggett (D) said his office tried to negotiate reforms in disability with the police union but encountered resistance from it. Union leaders did not return calls or e-mails seeking comment.