Many local courthouses across the nation are unsafe and overcrowded, and people working in them allege that long-neglected facilities are making them sick with everything from respiratory problems to cancer.

Flaking asbestos, peeling paint, black mold, a lack of ventilation and violations of modern building and fire codes are among the hazards, according to courthouse personnel, as well as legal actions and workers’ compensation claims filed in several jurisdictions from Boston to Los Angeles.