The aerospace, rail, and mass transit industries present unique sealing challenges due to their harsh sealing environments and critical nature. Long service life is essential, however these industries also need rubber parts that support passenger safety and comply with government regulations as well as original equipment (OEM) standards for flame, smoke, and toxicity (FST). The NFPA 130 is the standard for fixed guideway and passenger rail systems. This is the standard the majority of manufacturers in the USA are adapting to The European standard (EN45545-2) has similar requirements, and it is important to verify which standard is being applied to a particular project. There may be additional testing requirements needed, and the most common testing requirements are listed below.