oil refinery

access air attributes blue business catalytic catwalk chemical chemicals clean clouds column corporate corporation cracking danger distillation electric employees employment engineer environment equipment exchanger exchangers factory fumes furnace gas gauges generator handrails hatch hazard health heat heavy industrial industry manufacturing market metal money oil old operation operator pattern petroleum pipe pipeline pipes piping post pressure process profit protection pump quality refinery relief rust safety sky stack stairs stairwell steps tubes union unit valves vessel vessels walkway workplace