Steel Superstructures : Steel superstructures are used to support equipment, lines, and switches in substations as well as transmission and distribution line towers and poles
US Department of Labor, Electric Power eTool: Glossary of Terms, Occupational Safety & Health Administration OSHA, Washington, D.C., USA 2010. https://www.osha.gov/SLTC/etools/electric_power/gl ossary.html, (OSHA/ Electr Pwr - Amer) {618}