A broken blood pressure gauge used as a prop led to a mercury-spill crisis at the set of CBS' Guiding Light Thursday morning, a rep for the long-running soap opera tells TVGuide.com, resulting in the cast and crew being quarantined on the midtown Manhattan studio's sixth floor for hours. Hazmat containment personnel were deployed to the set, where they "bundled" the poisonous liquid metal and scanned anyone who was in the vicinity of the spill for traces of mercury. Production resumed by midday, although no one is allowed on the show's hospital set, where the mercury leaked, for 24 hours. How did the sphygmomanometer break? My guess: Jonathan and Tammy are just that exciting together.