Monitor transportation and storage of flammable and other potentially dangerous products to ensure that safety guidelines are followed. Monitor equipment functioning, observe temperature, level, and flow gauges, and perform regular unit checks to ensure that all equipment is operating as it should. Control operation of compressors, scrubbers, evaporators, and refrigeration equipment to liquefy, compress, or regasify natural gas. Start and shut down plant equipment. Record, review, and compile operations records, test results, and gauge readings such as temperatures, pressures, concentrations, and flows. Adjust temperature, pressure, vacuum, level, flow rate, or transfer of gas to maintain processes at required levels or to correct problems. Clean, maintain, and repair equipment, using hand tools, or request that repair and maintenance work be performed. Collaborate with other operators to solve unit problems. Determine causes of abnormal pressure variances, and make corrective recommendations, such as installation of pipes to relieve overloading. Read logsheets to determine product demand and disposition, or to detect malfunctions. Test gas, chemicals, and air during processing to assess factors such as purity and moisture content, and to detect quality problems or gas or chemical leaks. Contact maintenance crews when necessary. Change charts in recording meters.