When should extra heavy pattern fittings be used?

Extra heavy pattern fittings are specifically designed to handle higher pressure levels and provide stronger connections in piping systems. These fittings are often utilized in circumstances where the operating pressures exceed 175 psi, as they offer greater strength and durability compared to standard fittings. This capability makes them suitable for industrial or commercial applications where pressure demands are significantly high.

In scenarios where pressures surpass this threshold, using extra heavy pattern fittings ensures the integrity and safety of the system. They are made to withstand the stresses associated with heavier loads and high-pressure situations, thus minimizing the risk of failure at connection points.

The other options do not address the specific technical requirement for using extra heavy fittings as they focus on factors such as personal choice, aesthetics, or residential applications, where the pressure demands do not typically warrant such reinforced fittings.