The adult and child were on the second-floor balcony of the residence in the 100 block of Kennedy Street near Roy-Pitz Avenue in Chambersburg when the railing gave way just after 4:30 p.m. on Oct. 19, according to officials with the department.
The pair fell approximately 12 feet and emergency crews were called to the scene at 4:46 p.m., Chambersburg Fire Department Chief Dustin Ulrich explained.
Lack of "structural integrity" of the balcony led to dry rot causing the railing they were holding onto to crumb at the base, Ulrich said.
Crews established a landing zone for a Life Lion helicopter in the 400 block of Grant Street so the child and adult could be rushed to a trauma center.
Their injuries are serious but are not life-threatening, according to Ulrich.
The public was asked to avoid the area for a few hours following the incident.
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