The Biden administration has exempted most employers from long-awaited rules for protecting workers from the coronavirus, angering labor advocates who had spent more than a year lobbying for the protections. The Labor Department included only health care workers in its new emergency temporary standard published Thursday. The rules require employers to draw up a virus protection plan, and tighten requirements for recording and reporting COVID-19 cases among workers. They also require employers to provide workers with paid time off for COVID-19-related absences, including getting vaccinated and recovering from the shot’s side effects. Rather than issue mandatory rules for other workplaces, the Biden administration released new nonbinding guidance that relaxed some recommendations.