A court injunction filed by Santa Clara County today has barred about 500 employees from participating in a strike set for Tuesday by a union representing about 9,000 of its workers.

The county filed the injunction in Santa Clara County Superior Court today after Service Employees International Union Local 521 announced Tuesday's strike due to unfair labor practices, economic inequality, public safety, a labor shortage and other issues.

The county had asked the court to have 2,106 of its "essential workers" in the union that work in areas including the public health and safety sectors from going on strike, county spokeswoman Gwen Mitchell said.

But Judge Joseph Huber in his decision today approved the injunction only for about 500 of the essential workers as recommended by the state Public Employment Relations Board.

The workers who cannot go on strike include emergency dispatchers, social workers, respiratory care practitioners and jail employees.

Huber also asked for the county and union to determine if additional employees should be added to the list of those barred from taking part in the strike.

Union officials said they want the county to address a 35 percent staff shortage within the 911 Communications Department, as well as a looming labor shortage where about 2,000 workers will reach retirement age in five years.

Santa Clara County workers represented by the union said they have been holding many public actions to highlight the multiple crises facing the county, but the county's management has not taken adequate steps to meet the challenges.

Union officials allege that county management has chosen not to work with its workers to implement proposals that put the community first, but instead has chosen to interfere in union business.

County management has eliminated alternative work hours as a form of retaliation, singled out SEIU leaders with unfavorable reports and has changed sick leave policies to scare workers out of striking, according to union officials.

The union has filed four charges against the county with the Public Employment Relations Board, union officials said.

The latest contract between the union and county expired on June 21 and was extended two days after, according to union and county officials.

The union plans to strike starting 6 a.m. Tuesday unless an agreement is reached, union officials said.