Electrochemical Sensor Technology

Electrochemical sensors are a widely used sensor for work place gas monitoring.  Ethylene Oxide diffuses into the sensor, through the back of the porous membrane to the working electrode where it is oxidized or reduced. This electrochemical reaction results in an electric current that passes through the external circuit. In addition to measuring, amplifying and performing other signal processing functions, the external circuit maintains the voltage across the sensor between the working and counter electrodes for a two electrode sensor or between the working and reference electrodes for a three electrode cell. At the counter electrode and equal an opposite reaction occurs, such that if the working electrode is an oxidation, then the counter electrode is a reduction.

The ChemDAQ Difference

The most common method to detect EtO is using electrochemical gas sensors which determine the current by measuring the rate of oxidation of EtO entering the sensor. EtO is a difficult gas to oxidize and so the EtO sensor must be very active, but such activity means that the bare sensor is susceptible to cross sensitivity to other gases that are more easily oxidized than EtO. People who have used EtO sensors from other suppliers are usually well aware of the cross-sensitivity problems that make EtO sensors notorious. ChemDAQ is the only company to have developed a filter for the sensor that prevents most of these interfering gases, including alcohols, carbon monoxide and most VOCs from reaching the sensor. This patented filter technology is included with every ChemDAQ EtO sensor and is the reason why ChemDAQ customers no longer look at EtO sensors in the same apprehensive way as their non-ChemDAQ counterparts. As with all of our sensors, our EtO sensors are calibrated with Ethylene Oxide, the target gas, providing better accuracy and specificity at occupational safety levels.

Steri-Trac 2+ Area Monitor (ST2+)

ChemDAQ's continuous monitor ensures your employees are safe in real-time. The ST2+ fixed monitor pairs with our EtO E-Cell sensor to continuously monitor and alert you to hazardous vapor levels in the air. This provides a fully integrated, intuitive system with flexible options for monitoring Ethylene Oxide exposure.

• Real-time measurement of vapor concentration in parts per million, while simultaneously calculating an 8 hour and 15 minute time weighted average (TWA)

• Easy to use "plug & play" setup with no installation required

• Visual and audible alerts are factory set to meet regulatory requirements, but are customizable to user preference

• "Impending" alerts warn as exposure is approaching unsafe limits allowing for proactive measures

• Data collected and stored in .csv format and is downloadable for analysis and reporting purposes

*ST2+ can be paired with ChemDAQ's Intrinsically Safe EtO sensors for use in hazardous environments

Data Acquisition System (DAQ)

The CHEMDAQ Data Acquisition System (DAQ) is a PC-based computer software system that provides continuous collection, display, analysis, and storage of Ethylene Oxide (EtO) or other gas exposures for up to 32 Area Monitors. This integrated system helps to monitor immediate and long term exposure of Ethylene Oxide and other gases. 

As an area monitoring and archival system, the CHEMDAQ Data Acquisition System is not intended to meet the OSHA 29CFR1910·1047(d) requirement for initial and follow-up personnel monitoring. The Area Monitor units of the Data Acquisition System fulfill the requirements of OSHA 29CFR1947(h)(2) for alerting employees in emergency situations.

The Data Acquisition System (DAQ) increases the effectiveness of individual Area Monitors by:

• Centralizing all monitoring data;

• Comparing all exposure levels to OSHA standards and requirements for user safety;

• Alarming when these levels are exceeded or may be exceeded if current concentrations continue (Impending Alerts);

• Documenting and storing all Area Monitor activity for current review and/or later retrieval; and

• Storing exposure, maintenance and calibration histories of each Area Monitor unit.

Remote Video Display (RVD)

The Remote Video Display duplicates the display from the DAQ computer to a video monitor, that workers and supervisors can view all sensors from a single location. Do you have a door leading into your monitored area? Putting a Remote Video Display outside of it will let everyone know it is safe to enter before entering.

Remote Display Repeater (RDR)

Do you want to see a rooms exposure levels from a safe distance? Our remote display is perfect for you to keep yourself clear from over-exposure to any of our chemicals. The remote display duplicates information received from the fixed monitor, which can connect to one or more remote displays. Remote displays are typically wall mounted outside of monitored areas to warn personnel of gas levels prior to entry.