1. Research Faculty and Associate Director of Construction Safety Research Alliance, Dept. of Civil, Environmental, and Architectural Engineering, Univ. of Colorado Boulder, 1111 Engineering Dr., UCB 428, Boulder, CO 80309-0428 (corresponding author).
2. President, Teaching Scholar, and Beavers Endowed Professor of Construction Engineering, Dept. of Civil, Environmental and Architectural Engineering, Univ. of Colorado at Boulder, 1111 Engineering Dr., Boulder, CO 80309-0428.