The U.S. Court of Appeals for the First Circuit recognizes medical monitoring as a viable tort remedy. But that doesn’t mean medical monitoring class actions are easy to win in that jurisdiction, as the appeals court reminded a group of former Raytheon Company employees Tuesday.

In a 21-page decision, the First Circuit affirmed the dismissal of a class action lawsuit seeking to require Raytheon to set up a trust fund to pay for medical screening of plant workers who say they were exposed to dangerous beryllium dust and fumes. Affirming U.S. District Judge Mark Wolf in Boston, the appeals court ruled that the plant employees failed to show they’d suffered the sort of harm required to put a defendant on the hook for medial monitoring.