This paper summarizes a series of large-scale outdoor and indoor LNG pool fire experiments conducted at Sandia National Laboratories in Albuquerque, New Mexico. Two outdoor LNG spills on water with resulting pool fires of 21 m and 56 m in diameter were conducted to improve hazard predictions by obtaining measurements of flame height, smoke production, and burn rate. The experimental data indicates that LNG pool fires on water display different behavior than those on land by producing less smoke. Surface emissive powers of up to 286 kW/m(2), flames heights of up to 146 m, and burn rates of about 0.147 kg/m(2) s were measured. Discussion is provided on the observed behavior of the two outdoor tests with regards to smoke production, wind effects, and hydrate production. The large-scale indoor experiments used a 3-m diameter gas burner with methane fuel to assess flame height to fire diameter ratios as a function of non-dimensional heat release rates for extrapolation to large-scale LNG fires. A flame height correlation was developed from this data. (C) 2015 The Combustion Institute. Published by Elsevier Inc. All rights reserved.