Which gasket material is deemed unacceptable for use in gas piping flanges?

Rubber gaskets are deemed unacceptable for use in gas piping flanges due to their properties that can lead to failures in gas-tight seals. In environments where they are exposed to gas, rubber can degrade or react with the substances it comes into contact with, leading to deterioration over time. This degradation can cause leaks, which pose significant safety hazards in gas applications.

In contrast, fiberglass, metal, and silicone materials are designed to withstand the conditions present in gas piping and provide reliable sealing solutions. Fiberglass offers high strength and resistance to various chemicals, metal gaskets are durable and can handle extreme pressure and temperature fluctuations, and silicone gaskets maintain their flexibility and integrity over a range of temperatures, making them suitable choices for this application. Therefore, when selecting materials for gas piping flanges, ensuring the choice does not include rubber is essential for safety and functionality.