If you're looking for the actual PDF document, I recommend visiting the API website or searching for authorized distributors who provide access to API standards.
It specifically addresses a niche but vital category of storage: . These are distinct from standard ASTs (API 650/620) because they incorporate passive fire protection (e.g., concrete, masonry, or thermal insulation systems) to withstand a severe fire exposure without failing or causing boiling liquid expanding vapor explosions (BLEVEs). api 2510a pdf portable