Emergency relief systems, process controls

Windsock to determine which way wind is blowing Automatic temperature controls to prevent overheating Pressure relief system to deal with excessive pressure Gauges and indicators to provide information about the state of the process Flares and scrubbers to burn off or neutralize released gas Positive pressure and filtered air in some units to protect employees Spare tank for runoff Emergency showers Eyewash fountain... 

Reduction Process control, emergency plan, physical barriers, safety relief valves Use of ignition suppression, procedural system... 

The use of appropriate instruments to monitor equipment operation and relevant process variables will detect, and provide warning of, undesirable excursions. Otherwise tliese can result in equipment failure or escape of chemicals, e.g. due to atmospheric venting, leakage or spillage. Instruments may facilitate automatic control, emergency action such as coolant or pressure relief or emergency shutdown, or the operation of water deluge systems. 

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