The union representing California State University faculty announced Wednesday that its members have voted to authorize a two-day strike should negotiations over salary, class sizes and other issues continue to stall.

The vote could result in two-day rolling strikes at the 23 campuses, most likely beginning in the fall, according to the California Faculty Assn.

The union represents 23,000 Cal State professors, lecturers, librarians, counselors and coaches. About 53% of the total faculty are union members.

Union officials said 70% of the group’s 12,501 members participated in the vote. Of those, 95% voted to approve the plans.

The action does not mean a strike will be called, but it gives the union authority to do so if negotiations fail with Chancellor Charles Reed. The vote comes as Cal State has suffered severe cuts in state funding — $750 million this fiscal year, with the potential for an additional $200-million reduction next year if voters fail to approve a tax initiative backed by the governor on the November ballot.

The Cal State system has raised tuition, offered fewer courses and turned away thousands of students because of budget cuts.

The union, which said faculty members haven’t received raises since 2007, is asking for 1% pay increases for each year of the new contract, more control over class sizes and greater stability for faculty with temporary contracts, among other proposals.

“The CSU faculty have run out of patience,” said union President Lillian Taiz, a history professor at Cal State Los Angeles. “It’s time to address seriously the issues before us so our faculty can get back to the business of providing quality education to the students of California.”

Cal State officials said the union’s demands would cost the system more than $500 million. They are proposing to maintain current salary levels for 2011-12 with the potential for reopening negotiations for future years if financial conditions improve.

The three-year contract expired in June 2010 and mediation efforts broke down last month. The two sides are expected to meet this week.

If they do not reach an agreement, a neutral fact-finder will be appointed to seek a resolution. If no settlement is reached, the union has legal authority to stage the walkout.

Union leaders said they understood the possible adverse effect a strike could have on students, but contended that such an action would bring attention to their struggles as well.

“It’s safe to say that what is going on now in the system is having a more profound effect on our students than losing a day of classes,” Taiz said. “What students should understand is that we are all in this together.”

stephen.ceasar@latimes.com