The Federal Energy Regulatory Commission (FERC) and Pipeline and Hazardous Material Administration (PHMSA) require vapor dispersion modeling as part of a siting analysis for liquefied natural gas (LNG) facilities. Guidance issued by PHMSA, in consultation with FERC, establishes a protocol for the scientific assessment, verification, and validation of vapor dispersion models. This thesis provides an evaluation of the Fire Dynamic Simulator (FDS), Version 5.5.1, for LNG vapor dispersion hazards. The scientific assessment demonstrates that FDS is capable of modeling LNG vapor dispersion hazards, but raises potential limitations associated with the specification of the source term, initial conditions, and boundary conditions; the verification calls for third party confirmation of modeling results; and the validation recommends a safety factor of up to 2 for modeling LNG vapor concentrations in unobstructed flow fields and a safety factor of up to 3 for modeling LNG vapor concentrations for obstructed flow fields.