What conditions would prohibit the use of a delivery hose assembly for unloading liquefied compressed gases?

The use of a delivery hose assembly for unloading liquefied compressed gases is critical to ensure safety and proper function during the operation. A delivery hose assembly that shows signs of damage, such as soft spots and bulging, indicates a compromised structural integrity. These conditions can lead to potential leaks or ruptures, posing serious risks of fire, explosion, or exposure to hazardous materials.

Soft spots in the hose can develop from fatigue, improper handling, or age, making the material weak and susceptible to failure under pressure. Bulging suggests that the internal reinforcement of the hose is inadequate or has failed, which also heightens the risk of a rupture.

Additionally, damage to the cover, especially when combined with soft spots and bulging, can significantly increase the potential for leaks and operational failures. The combination of these factors—damage to the cover, soft spots, and bulging—truly represents a situation where safety precautions demand that the hose assembly be taken out of service.

In summary, the presence of any or all of these conditions indicates that the delivery hose assembly is not safe for use, aligning perfectly with the guidelines established in NFPA 58 to ensure safe handling of liquefied compressed gases.