Mark III is a privately held corporation that specializes in engineering, maintenance, fabrication, construction and air pollution in the oil, gas, chemical, paper and aggregate industries. The company provides general engineering and detailed design services, including plant layout, civil, structural, mechanical, instrument and electrical. It also provides maintenance, construction and field services. It fabricates pipes, structural, meter and process skids in accordance with applicable codes. The company uses the American Society of Mechanical Engineers' Code Stamp R for vessel rework and repair. It is associated with Airtek Engineering and Construction of Troy for precipitator installation and rebuild. Mark III, headquartered in Sealy, Texas, maintains a divisional office in Soda Springs, Idaho.