Balance with blast gates--a precarious balance

For most dust and fume control systems, balancing without dampers and blast gates is by far the preferred choice. The advantages of blast gates, although true, are highly exaggerated, and the limitations of their use not generally recognized. They are advantageous to the vendor or contractor, not to the owner. A major exception to this position is the type of system where dampers or blast gates are used as on-off valves. Even in such cases, their operation should be interlocked with the process if practical.