Safety Considerations

Safety is a key consideration in any processes involving flammable substances such as ethylene oxide. When mixed with high levels of air, ethylene oxide becomes highly volatile. Ethylene oxide can be dangerously explosive in concentrations as low as 3% by volume. This is why redundant control logic monitors critical process parameters within the PLC and raises alarms if one of the critical parameters is outside of the range. Cycle definition consistency checks detect and notify Production Managers of possible flammable conditions before the process is even started.

In addition, remote IO consists of several panels that include standard and intrinsically safe IO modules connected to the PLC over a redundant media network. IO modules are powered from intrinsically safe power supplies. Each chamber has one IO node with its own 24 VDC power supply and communication module.

Sensors are placed in any areas that could potentially be polluted by ethylene oxide. Gas detectors monitor the levels in order to generate alarms if any leaks are detected. Ethylene oxide removed from the chamber during the cycle must be treated and disposed in an environmentally safe and ethical manner. This can be achieved by scrubbers, burners or oxidation methods.