These requirements cover below-grade vaults intended for the storage of flammable or combustible liquids in an aboveground atmospheric tank. Below-grade vaults are designed to contain one aboveground tank which can be a compartment tank. Adjacent vaults may share a common wall. The lid of the vault may be at or below-grade. Below-grade vaults are constructed of a minimum of 6 inches (152.4 mm) of reinforced concrete or other equivalent noncombustible material and form a complete@ liquid-tight enclosure that does not allow external ground water to permeate through the vault walls. Below-grade vaults can be evaluated as secondary containment vaults. Below-grade vaults covered by these requirements do not include an evaluation of components@ such as ventilation equipment@ leak detection and monitoring equipment@ overfill protection equipment@ and access ladders. Below-grade vaults are intended for installation and use in accordance with the manufacturer's instructions and the following fire codes: the Flammable and Combustible Liquids Code@ NFPA 30@ the Automotive and Marine Service Station Code@ NFPA 30A@ and the Uniform Fire Code@ Appendix II-J. Below-grade vaults covered by these requirements may be shipped in parts that require final assembly in the field. When field assembly is required@ detailed installation instructions shall be provided. These requirements do not cover seismic loading. A product that contains features@ characteristics@ components@ materials@ or systems new or different from those covered by the requirements in this Standard@ and that involves a risk of fire@ electric shock@ or injury to persons shall be evaluated using the appropriate additional component and end-product requirements to determine that the level of safety as originally anticipated by the intent of this Standard is maintained. A product whose features@ characteristics@ components@ materials@ or systems conflict with specific requirements or provisions of this Standard shall not be judged to comply with this Standard. Where appropriate@ revision of requirements shall be proposed and adopted in conformance with the methods employed for development@ revision@ and implementation of this Standard.