Corrosion-resistant Tanks
These are base steel tanks (UL 58 primary or secondary types) provided with an external corrosion-protection system constructed and investigated to UL 1746, “External Corrosion Protection Systems for Steel Underground Storage Tanks.” These tank constructions may be Cathodic (Part I), Composite (Part II), Jacketed (Part III) or Coated (Part IV) types, and are suitable for containment of general fuels and similar flammable and combustible liquids, as identified in the (*) liquid ratings:
Cathodically protected underground tank for (*) — A steel primary tank with a pre-engineered, galvanic-type cathodic-protection system (anode pack with connecting wires and dielectric coating and bushings) that provides external corrosion protection.
Cathodically protected type ($) secondary-containment underground tank for (*) — A steel Type I or Type II secondary-containment tank with a pre-engineered, galvanic-type cathodic-protection system (anode pack with connecting wires and dielectric coating and bushings) that provides external corrosion protection.
Coated underground tank for (*) — A steel primary tank covered directly (bonded) with a thin nonmetallic cladding (min 70 mil PUR) which provides external corrosion protection.
($) secondary-containment coated underground tank for (*) — A steel Type I or Type II secondary-containment tank covered directly (bonded) with a thin nonmetallic cladding (min 70 mil PUR) which provides external corrosion protection.
Composite underground tank for (*) — A steel primary tank covered directly (bonded) with a thick nonmetallic cladding (min 100 mil FRP) which provides external corrosion protection.
($) secondary-containment composite underground tank for (*) — A steel Type I or Type II secondary-containment tank covered directly (bonded) with a thick nonmetallic cladding (min 100 mil FRP) which provides external corrosion protection.
Jacketed underground tank for (*) — A steel primary tank completely contained within a nonmetallic external tank jacket (min 100 mil FRP, PUR, PE or Polyurea) which provides secondary containment, interstitial leak monitoring, and external corrosion protection.
Jacketed tertiary-containment underground tank for (*) — A steel Type I or Type II secondary-containment tank completely contained within a nonmetallic external tank jacket (min 100 mil FRP, PUR, PE or Polyurea) which provides tertiary containment, interstitial leak monitoring, and external corrosion protection.
