A Photometric Method for Evaluating Carpet Wear

Abstract

To measure changes in carpet appearance due to traffic, we have built an instrument that directs a beam of light onto the carpet surface and measures the intensity of the scattered light using a photometer. Traffic increases reflection because of the generation of more bent filaments in the tufts, and the change is used as an index of how well the carpet resists distortion from mechanical stresses imposed by traffic. A correction for the initial brightness of the carpet is necessary. Angles of incidence and detection can be varied, and part of this work is aimed at finding the best combination of these angles. The agreement between appearance retention ratings obtained with the in strument and subjective visual ratings is encouraging.