Here is a Philadelphia Inquirer article about efforts by Republicans in Pennsylvania's state legislature to outlaw strikes by public mass transit employees.
I'm surprised by the description of other states' laws on this subject. I was under the impression that, since the initial growth of public employee unions in the 1960s and '70s, as described in the article, they had established their right to strike everywhere. But, apparently, the People's Republic of Pennsylvania is rare in allowing that.
I hope that right-minded folks in Harrisburg are successful in returning some sanity to that situation.