How many brass washout plugs are required on a miniature boiler with less than 12" ID and less than 10 sq ft heating surface?

For a miniature boiler with an internal diameter (ID) of less than 12 inches and a heating surface of less than 10 square feet, the requirement is defined by specific regulatory standards related to safety and maintenance. In this case, the correct answer is that two brass washout plugs are required.

Brass washout plugs are essential for allowing access to the internals of the boiler for cleaning, inspection, and maintenance. The number of plugs needed is dictated by the boiler's design and operational requirements. A boiler of this size typically benefits from having two strategically placed plugs to facilitate effective cleaning and maintenance while ensuring that no areas are left unchecked that could lead to operational inefficiencies or hazards.

In the context of the options provided, determining the correct number of plugs helps ensure that the boiler operates safely and efficiently while complying with the relevant codes and standards. Proper maintenance access through these washout plugs is crucial for the longevity and reliability of the boiler system.