43 Pa. Stat. § 213.16
Nothing in this act shall be construed to require an individual employe to render labor or service without his consent or to make unlawful the quitting of his labor or service or the withdrawal from his place of employment, unless done in concert or in agreement with others and in violation of the provisions of this act. No court shall have power to issue any process to compel an individual employe to render labor or service or to remain at his place of employment without his consent. It is the intent of this act only to forbid employes to leave their employment in concert or to cause a work slowdown or stoppage in concert in violation of the provisions of this act and to forbid an employer to lockout his employes in violation of the provisions of this act.
43 P.S. § 213.16