Portable Pipe Hangers Canada / MJ International - Rooftop Pipe, Duct & Equipment Supports / Hazmat management, spill control & secondary containment. Rooftop Duct and Pipe Supports, Rooftop Cross-Over Bridges, Rooftop Access Stairs, Rooftop Service Platforms, Rooftop Walkways, Rooftop Wall Ladders, Rooftop Seismic Applications