What is the purpose of a Siamese connection in firefighting?

The purpose of a Siamese connection in firefighting is to combine two hoses into a single line. This allows firefighters to draw water from two sources simultaneously, which can significantly increase the flow rate when larger volumes of water are needed, such as during a firefighting operation. Using a Siamese connection can also enhance pressure, improving the efficacy of water delivery to the firefighting hoses.

A Siamese connection is especially useful in situations where one hydrant may not provide sufficient water flow by itself. Firefighters can leverage this setup to maximize their resources and ensure that they can effectively combat fires, particularly in larger incidents where water demand is critical.

The other options focus on different aspects of firefighting equipment. Increasing the diameter of a water outlet pertains to the configuration of nozzles or hoses to enhance flow, adapting fittings concerns compatibility of thread types for connectivity, and reducing excess pressure would involve pressure regulators or relief valves, which are unrelated to the primary function of a Siamese connection.