Which of the following describes how a technician can determine the trade size of a pipe?

To determine the trade size of a pipe, measuring the inside diameter is the most effective method because the trade size correlates primarily with the internal dimensions of the pipe. Various piping systems, such as those used in fluid power, often have standard trade sizes that are based on the nominal inside diameter. This measurement is crucial for ensuring compatibility with fittings, valves, and other components in the system, which are designed to fit specific sizes.

Using a caliper to measure the inside diameter provides the technician with the necessary information to reference against standard pipe charts, which outline the trade sizes associated with given internal dimensions. Understanding the inside diameter is essential for proper fitting and function within fluid systems, impacting flow rates and overall system efficiency. This method effectively ensures that the correct size and type of pipe can be selected for a specific application.