Hamilton dissolved oxygen sensors achieve North American Ex approval for hazardous environments

Hamilton today announced that its VisiFerm mA and VisiTrace mA dissolved oxygen sensors have received North American Ex approval, enabling safe operation in hazardous and explosive environments across the United States and Canada.

The certification confirms that the sensors meet the requirements for intrinsically safe process control equipment used in classified hazardous locations. The approval was granted through CSA Group and includes certification against CSA, UL, and FM standards, providing coverage across all major North American regulatory frameworks for hazardous-area instrumentation.

With this milestone, Hamilton’s dissolved oxygen sensing technology can now be deployed in facilities where flammable gases, vapors, dust, or fibers may be present. These environments are common in industries such as chemical manufacturing, energy production, and other industrial processes where safety-certified instrumentation is required.

The certification applies to Hamilton’s VisiFerm mA and VisiTrace mA sensors, loop-powered devices designed for reliable dissolved oxygen monitoring in demanding process environments. The sensors operate via a 4–20 mA HART interface and are approved for intrinsically safe installations when deployed according to the certified control drawings.

This approval represents an important step in expanding the reach of our dissolved oxygen sensing portfolio.

By achieving hazardous-area certification for North America, we are enabling customers in highly regulated industrial environments to benefit from Hamilton’s proven sensor technology while meeting strict safety requirements.”

Emanuel Souto, Global Product Manager, Hamilton 

Dissolved oxygen monitoring plays a critical role in many industrial processes, helping operators maintain process stability, product quality, and operational efficiency. With hazardous-area certification now in place, Hamilton’s sensors can support these measurements in facilities that previously required specialized instrumentation for explosive atmospheres.

The newly approved sensors are certified for use in Class I, II, and III hazardous locations and comply with internationally recognized standards for equipment protection by intrinsic safety. In addition to this new certification, the sensors have already been certified for hazardous environments under ATEX, IECEx, UKEx, and EAC standards since 2019, with this latest milestone extending coverage to North America. By extending its sensor portfolio into hazardous environments, Hamilton continues to support customers across biotechnology, chemical processing, and industrial manufacturing with reliable process analytics designed for demanding applications.