What must aboveground containers have to comply with safety regulations for their relief valve discharge?

Aboveground containers must have their relief valve discharge unobstructed to the open air to comply with safety regulations. This requirement is crucial because it ensures that any gas released through the relief valve can dissipate safely into the atmosphere without accumulating in a confined space, which could pose a serious explosion or fire hazard.

Allowing the discharge to flow freely into the open air facilitates the proper functioning of the relief valve, ensuring that excess pressure is safely released. This is especially important for LP gas containers, where the buildup of pressure could lead to catastrophic failures if not managed properly.

In contrast, redirecting the discharge downwards, placing it at any height, or positioning it against a wall could create hazardous situations by either trapping gas in a confined space or allowing it to accumulate near other structures or equipment, increasing the risk of ignition and fire incidents.