A 3-dimensional scale jointly proposed in 2013 by NIST and the U.S. Forest Service, to predict the risk to particular locations where urban settlements adjoin wildlands (the wildland urban interface, or WUI). Ratings from 1 to 4 (with 1 no risk) are assigned to the risk of ignition from embers (E1 to E4), and to the risk of ignition from thermal radiation or direct flame (F1 to F4). The third dimension is provided by 4 categories of fire resistance of buildings and landscaping. The purpose of the scale is “to explicitly identify WUI areas that have a fire problem, as opposed to areas that meet housing density or wildland vegetation requirements as is frequently done.” “The proposed WUI-scale is developed with the primary objective of reducing the ignition risk of buildings in the WUI.”
Alexander Maranghides and William Melldoi.
NIST Technical Note 1748.
Framework for Addressing the National Wildland Urban Interface Fire Problem – Determining Fire and Ember Exposure Zones using a WUI Hazard Scale.
U. S. Dept. of Commerce, January 2013.
Copyright © 2014 Sizes, Inc. All rights reserved.
Last revised: 11 April 2014.