Continuous gas monitoring warns of leak in exhaust, saving employees from high-level exposure to Ethylene Oxide.

December 2008

A west coast hospital customer contacted ChemDAQ® Technical Services to report an Ethylene Oxide Area Monitor alarm. When SPD staff started an EtO sterilization cycle the Steri-Trac® Area Monitor went into alarm reporting 50ppm of ethylene oxide in the work area. A new sterilizer had recently been installed in the department.

The hospital investigated the situation and determined that a vent line to the abator was loose. They repaired the vent line which corrected the situation.

Although ChemDAQ’s Envirocell sensor modules are designed to tolerate more than 50ppm of ethylene oxide we priority shipped calibrated replacement sensor modules to assure the integrity of the system until the next scheduled sensor exchange.

Case Study Analysis

Because the customer was using a ChemDAQ® continuous gas monitoring system for ethylene oxide detection, the leak was detected and corrected in a very short time. If they were not using real-time gas detection, the employees would have been exposed to high concentrations of ethylene oxide for an extended period of time. Even if EtO badges were used immediately after installing the new sterilizer, a loose vent line may not have leaked for several weeks or months after the initial install. There’s no assurance the badges would have detected ethylene oxide levels indicating a problem.

Let’s assume the badges did detect EtO in the workers’ breathing zone. Typically the results from badging are not received for 2 to 3 weeks after they are shipped to the lab. During this time the workers were exposed to as much as 50ppm of ethylene oxide on a routine basis.

Fortunately this hospital chose to install continuous gas detection to protect their SPD workers. After the loose vent was discovered the Steri-Trac® continuous gas monitoring system provided immediate assurance that the leak had been corrected.

When working around toxic gases used for low temperature sterilization:

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