| Accroven | Javelina |
| Air Products & Chemicals | JGC |
| Alberta Pacific | Kaneb Pipeline |
| Alyeska Pipeline Service | Kerr-McGee |
| Amoco Oil Company | Lagoven |
| Ampol Refineries | M.W. Kellogg |
| Anadarko Petroleum Corporation | Magellan Midstream Partners |
| Atlantic LNG of Trinidad & Tobago | Marathon Oil Company |
| Atlantic Richfield Company | Maxus Venezuela |
| Badak | Merit Energy |
| BP America Production | Mesa Petroleum |
| BP Canada Energy Company | Mid-America Pipeline Company |
| BP Exploracion de Venezuela | Mobil Exploration |
| British Gas | North Atlantic Pipeline Partners |
| British Petroleum | Occidental Exploration & Production |
| Buckeye Partners | Occidental Petroleum |
| Calpine Power Services | Onquest |
| Caltex Petroleum Corporation | Operadora Cerro Negro |
| Cargill | OxyChem |
| Chevron | Paz Ashdod Refinery |
| Chevron Pipe Line Company | PDVSA |
| ChevronTexaco | Pennzoil |
| Cimarex Energy | Petro-Canada |
| Citgo Petroleum Corporation | Petron Corporation |
| Citizens Gas & Coke | Phillips Alaska |
| Coastal Petroleum Company | Phillips Petroleum |
| Coastal Refining | Pioneer Natural Resources |
| Colorado Interstate Gas | Praxair |
| Conoco | Rocky Mountain Natural Gas |
| ConocoPhillips | Saferco |
| ConocoPhillips Alaska, Inc. | SemGas |
| Copec | Sempra |
| Corpoven | Sempra LNG |
| Coskata | Shell |
| CXY Energy | Southern Natural Gas |
| Devon | Sun Refining & Marketing |
| Distrigas | Suncor Energy |
| Duke Energy Field Services | Tampa Electric Company |
| DuPont | Technigaz |
| Ecopetrol | Tejas Gas |
| El Dorado Chemical Company | Terranext |
| El Paso | Texaco |
| Engen Petroleum Ltd. | Texaco Pipeline |
| ENSTAR | Tractebel LNG North America |
| Epsilon Products | Tractebel Power |
| Equilon Enterprises | TransCanada Pipeline Company |
| Ethyl | Trident NGL |
| Evonik | Trinity Pipeline |
| Expro International Group | UEG Araucaria |
| Exxon Company | Union Oil |
| Firmenich Incorporated | Union Pacific Resources |
| Flare Industries | Valero |
| Florida Power & Light | Vietnam Oil & Gas Corporation |
| Frontier Refining | Virginia Indonesia |
| Great Valley Ethanol | Westcoast Energy |
| Interprovincial Pipeline | Wisconsin Gas |
| Irving Oil | Yellowstone Pipe Line |
| Jacobs Canada | Yukon Pacific |
| Jantesa |
| AB Lummus Global | Mustang Engineering |
| ABB Randall Corporation | Nova Engineering |
| BE&K Construction Company | Parsons Process Group |
| Bechtel Corporation | Pitt-Des Moines (PDM) |
| Black & Veatch | Pritchard Corporation |
| Black & Veatch Pritchard | Processes Unlimited International |
| Brown & Root | Production Operators |
| CBS Engineering | Saipem |
| CEC Combustion Services Group | Sofresid Engineering |
| Chicago Bridge & Iron (CB&I) | Stratco |
| EDECO Engineers/Consultants | Sunkyoung Engineering & Construction |
| Engineering Design Group (EDG) | Technip |
| Engineering, Procurement & Construction | Willbros Engineers |
| Fluor Daniel | Williams Energy Services |
| Fluor Mideast Limited | Williams Exploration and Production |
| Foster Wheeler | Williams Field Services Company |
| Fundy Engineering | Williams International Company |
| Jacobs Engineering Group | Wilpro Energy Services |
| Kellogg Brown & Root | WorleyParsons |
| MPR Associates |
| City of Rio Vista | U.S. Department of Energy (DOE) |
| Maryland Public Service Commission | U.S. Department of Labor (DOL) |
| Port of Long Beach | U.S. Department of Transportation (DOT) |
| Port of Los Angeles | U.S. Department of Transportation Pipeline and |
| San Diego County Office of Education | Hazardous Materials Safety Administration (PHMSA) |
| U.S. Coast Guard | U.S. Transportation Safety Institute (TSI) |
| American Petroleum Institute (API) | Iowa State University |
| ARCO Exploration and Production Technology | Mary Kay O'Connor Process Safety Center |
| Battelle, Pacific Northwest Division | PDVSA Services |
| Center for Chemical Process Safety (CCPS) | Pennsylvania State University |
| Centro de Investigacion, Educacion | Petroleum Environmental Research Forum (PERF) |
| Y Desarrollo (CIED) | Southwest Research Institute |
| Chevron Energy Technology | Texas A&M University |
| Atkins | J. Conner Consulting |
| Boots & Coots Services | James E. Smith & Associates |
| CH2M Hill | Kane Environmental Engineering |
| EDM Services | Kendrick Consulting |
| Environmental Audit | Loss Control Associates |
| Environmental Resources Management (ERM) | Pacific Municipal Consultants |
| EQE International | Packer Engineering |
| Global Risk Consultants | REDA |
| GWM Consulting | Risknology |
| Imxport Services Corporation | Rolf Jensen & Associates |
| J House Environmental |