What should couplings and fittings in a steel underground petroleum product storage system be rated for at minimum?

Couplings and fittings in a steel underground petroleum product storage system should be rated for a minimum of 150 pound malleable iron. This standard is established to ensure that the components can withstand the pressures and stresses involved in storing petroleum products safely. The 150-pound rating indicates that these fittings are capable of handling significant load and operational stresses without failing, which is crucial for the integrity of the storage system and the prevention of leaks or spills.

Choosing couplings and fittings with a lower rating could compromise the safety and reliability of the storage system, potentially leading to operational failures. The 150-pound rating also aligns with industry standards and regulatory requirements for underground storage tank systems, ensuring that the installation is compliant with safety regulations. Properly rated components are essential not just for functionality, but also for maintaining environmental protection and public safety.