How much should gas piping be sloped to prevent traps?

The recommended slope for gas piping to prevent traps is 1/4 inch for every 15 feet. This slope is essential for ensuring that any condensate or moisture that may accumulate within the gas piping can properly drain away and not create a blockage, which could lead to potentially hazardous situations. The appropriate slope helps maintain the integrity of the gas system and reduces the risk of gas leaks.

Other options present different slopes, but they do not align with the established guidelines in the National Fuel Gas Code. Slopes that are too steep, like 1 inch for every 10 feet, could lead to the piping being overly inclined, making installation difficult and potentially leading to mechanical failures or stresses on the piping. Each of these different slopes, therefore, may cause operational issues if not carefully controlled, further justifying why the specified 1/4 inch for every 15 feet is the industry standard for safely preventing traps in gas piping.