To avoid damaging the interstitial space, what is the maximum pressure the inner tank should be pressurized to?

Maintaining proper pressure in the inner tank during testing is essential to avoid damaging the interstitial space, which serves as a critical area that provides secondary containment. Pressurizing the inner tank to the correct level ensures that it can withstand potential leaks or structural issues without compromising the integrity of the interstitial space.

The appropriate maximum pressure for the inner tank is set at 5 psig. This level balances the need to perform effective leak testing while also preventing excessive stress on the tank structure and its components. If the pressure is too high, it could lead to deformation or rupture of the interstitial space, resulting in costly repairs and potential environmental hazards. Keeping the pressure within this standard also aligns with industry best practices and regulatory guidelines, ensuring safety and compliance in UST systems.

Pressurizing the tank beyond 5 psig could facilitate overstressing materials and joints, leading to damaging consequences. Therefore, knowing and adhering to this limit is vital for proper installation and retrofitting practices in underground storage tank systems.