Big City Balancing is a New York City air and hydronic balancing contractor staffed by Sheet Metal Workers Local 28 members. Its service list names Smoke Control Systems Technician work, stairwell pressurisation testing and Fire and Smoke Damper Technician inspection alongside conventional balancing, duct leakage testing and operating-room pressurisation. The firm states that its technicians hold ICB/TABB certification, the ANSI-accredited credential for smoke control systems work. It is one of very few New York City firms advertising the smoke-control technician credential explicitly.