When is it permissible to pipe a convection steamer drain into a trap?

Piping a convection steamer drain into a trap is never permissible due to the risk of creating a potential backflow situation that could contaminate the potable water supply and create health hazards. The drain from a steamer typically carries food waste and other debris that need to be properly disposed of, and routing this through a trap can lead to clogs, odors, and unsanitary conditions in the kitchen environment.

In commercial kitchens, the drainage systems must adhere to strict health codes and regulations to ensure food safety and hygiene. By not piping the steam drain into a trap, the equipment operates safely and effectively, maintaining the integrity of the entire plumbing system and preventing unwanted backflow or cross-contamination.

Options suggesting specific conditions or situations under which it may be permissible do not align with established safety protocols. Whether during maintenance, when using low-pressure steam, or even if the trap is independently vented, these situations do not mitigate the fundamental issue of the risk posed by improper drainage methods. Thus, the prohibition against connecting a convection steamer drain to a trap holds true in all circumstances.