An experimental technique is implemented to analyse the behaviour of a wet porous medium under the direct impact of a flame, and the possibility of its use as a thermal protection device. The data obtained show that relatively thin and light thermal protections, with moderate values of water consumption, can be developed, presenting high levels of protection. The presentation of the data in a dimensionless form provides a useful tool to estimate the thickness and the water content of the protective device that are needed for expected values of incident heat flux and prescribed time of protection. (C) 2003 Elsevier Ltd. All rights reserved.