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RKI is pleased to announce the availability of Hydrogen Cyanide (HCN) and Nitrogen Dioxide (NO2) sensors for the GX-3R Pro. These 2 sensors are in stock and are the latest in toxic gas options added to the line of GX-3R Pro sensors.

HCN is often a by-product of burning plastics and synthetic polymers. After plastics have burned, HCN will off-gas which makes monitoring HCN important for firefighters.
A GX-3R Pro configured to 4-gas plus HCN makes an ideal solution for firefighters.

The GX-3R Pro's HCN sensor has a range of 0 - 30.0 ppm.

NO2 is commonly generated from the burning of fuel, especially diesel fuel.

The GX-3R Pro's NO2 sensor has a range of 0 - 20.0 ppm.

There are two ways to order a GX-3R Pro with HCN or NO2. One is to order the instrument new and configured with one of these sensors. See the price list link below for part numbers and configurations. The second way is to add the sensor to an existing
GX-3R Pro.

HCN	NO2
ESR-A13D-HCN	ESR-A13D-NO2
0 - 30.0 ppm	0 - 20.0 ppm

Adding an HCN or NO2 Sensor to a GX-3R Pro
To add one of the new sensors to a GX-3R Pro, the instrument firmware will need to be updated. This can be done by using the USB to IrDA adapter (47-5084RK-01) and following the IrDA Reprogramming instructions which can be found on the link below.

Reprogramming the GX-3R Pro firmware

https://www.rkiinstruments.com/download/gx3r-reprograming/

Don't Forget the Sensor Filters
When ordering an individual sensor, make sure to also order the sensor's H2S scrubber at the same time. Both the HCN and NO2 sensors utilize an H2S scrubber filter disk to eliminate any interference from H2S. Ordering information for the sensor and scrubber filter disks are below. When buying a new instrument, the scrubber filter disk is included.

Scrubber Disk for HCN Sensor	Scrubber Disk for NO2 Sensor
33-7137	33-7134