Which of the following is NOT an example of a compressed-air (pneumatic) tool used on a construction site?

A brazing torch is not considered a pneumatic tool because it does not operate using compressed air. Instead, a brazing torch is a tool that uses a flame produced by a gas, typically a mixture of propane and oxygen or acetylene, to join metal parts together by melting a filler metal. This process relies on heat rather than air pressure, setting it apart from other tools listed that utilize compressed air for their operation.

In contrast, an air impact wrench, pneumatic nail gun, and air hammer are all designed to use compressed air to function. These tools leverage air pressure to deliver high torque or force, allowing for efficient fastening, nailing, or cutting tasks on construction sites. This distinction highlights the specific operational mechanisms of each tool, demonstrating why the brazing torch does not fit into the category of pneumatic tools.