Net Safety ST3 XChem Toxic Gas Sensors
Starting at $856.98

Not in stock. Usually ships in 4-6 weeks [?]

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  • SMART sensor technology
  • Lowest power consumption available
  • 2000ft sensor separation
  • 2 year warranty
  • Field selectable gas ranges
  • Fine-tuned specific
  • Designed for extreme industrial environments

This product is an accessory for the following products:

Net Safety M21 Millennium II Single Channel Transmitter
SMART sensor technology, -67 to 185°F temp range, full diagnostics with event and data logging
Net Safety M22 Millennium II Dual Channel Transmitter
Dual channel, SMART sensor technology, -67 to 185°F temp range
Net Safety M2B Millennium II BASIC Universal Transmitter
Delivers highly accurate monitoring of toxic and combustible gases, SMART sensor technology

The Net Safety ST3 XChem Toxic Gas Sensors series of SMART electrochemical toxic gas sensors provide high specificity, fast response, and long life. All ST3 sensors are part of the universal Millennium II Gas Detection platform and are compatible with the M21, M22, and M2B transmitters. Our latest design employs our "SimpleClick" sensor element replacement plus improved over-all performance and extremely low power consumption.

There's no longer the need to purchase multiple gas specific detectors. You have the option to utilize 1 or 2 toxic and/or combustible gas sensors on a single Millennium II transmitter and easily mix and match any of our sensor technologies.

SMART (Self Monitoring Analysis and Reporting Technology) sensors are pre-calibrated and easily connected to the transmitter which instantly recognizes a newly fitted sensor, automatically uploading it's specific configuration profile.

Sensor and transmitter continuously communicate digitally, giving you the confidence of stable, accurate protection with fast response times even over long separation distances.

The ST3 Series has been approved to international hazardous area safety standards.

The ST3 Series of toxic gas sensors are all internally temperature-compensated to their particular target gas and field-selected range in order to provide as stable a sample as possible to the sensing element. Humidity is also controlled through the use of an advanced diffusion process as gases pass through our specialized hydrophobic barrier.


Net Safety CCS-1 Combination Calibration/Rain Shield/Splash Guard Cup
Combination calibration/rain shield/splash guard cup
Net Safety CC-INLINE Calibration Adapter
In-Line Cup Adaptor for gas sensors

Mounting Bracket

Net Safety Gas Sensor/Flame Detector Pipe Mounting Kits
Pipe mounting kit - gas detectors and flame detectors (stainless steel)


Net Safety ST Replacement Sensors
Hydrogen sulfide, oxygen, or carbon monoxide replacement sensors


Please consider these optional accessories.

Net Safety SSK Sun Shade Kit
Pipe Mounted Sun shade kit/rain guard - stainless steel
Net Safety SSK-2 Sun Shade Kit
Sun shade kit for MLP & ML2 detectors - stainless steel - Requires UN-MK-1
Net Safety IPF-001 IP 66/67 Filter
IP 66/67 Filter for SX3 Series sensors
Net Safety Universal Duct Mount Assembly
Stainless steel universal duct mount assembly, 1M or 1.5M sampling pipe
Net Safety JB Series Junction Box
Termination box for flame detectors or for remote mounting gas sensors from transmitters