MSA 0800-177-MC Gas Detectors and Altair
Specifications
- Product Name: XCell Gas Detector
- Sensor Type: Electrochemical Sensor
- Cross-Sensitivity Data: Available for specific gases
Product Usage Instructions
- Understanding Cross-Sensitivity Data
Electrochemical sensors may be cross-sensitive to gases other than the target gas. Cross-sensitivities are additive, meaning the sensor reading combines concentrations of both gases present. - XCell CO Sensors
For XCell CO Sensors, the cross-sensitivity data provides scenarios with target gas concentrations, cross-sensitive gases, and corresponding readings. - XCell CO & CO-HC Sensors
These sensors provide cross-sensitivity data for various gases along with the applied concentrations and corresponding readings. - XCell HS & HS-LC Sensors
Similar to the CO sensors, these sensors have cross-sensitivity data for different gases along with applied concentrations and readings. - XCell SO (Single) Sensors
The single SO sensors offer cross-sensitivity data for specific gases with applied concentrations and resulting readings. - XCell SO (Two-Tox) Sensors
These sensors provide cross-sensitivity data for various gases similar to the single SO sensors. - XCell CO H-RES Sensors
Cross-sensitivity data is available for CO H-RES sensors with applied concentrations and readings for different gases. - XCell NO Sensors
For NO sensors, cross-sensitivity data includes applied concentrations and resulting readings for various gases. - XCell NH Sensors
Cross-sensitivity data for NH sensors includes applied concentrations and corresponding readings for different gases.
ALTAIR® 2X, 4XR & 5X Gas Detectors & ALTAIR io™ 4 Gas Detection Wearable
Electrochemical Sensor Cross-Sensitivity Data*
It is quite common for electrochemical sensors to be cross-sensitive to specific gases other than the target gas of interest. Cross-sensitivities are limited as much as possible by sensor design, but some interactions still exist. The tables below are a general guide to these common cross-sensitivities which can be used to understand gas detector readings in environments where multiple gases may be present.
Using Cross-Sensitivity Data
Below you will find multiple scenarios to aid in the use of the provided cross-sensitivity data. It is important to note that cross-sensitivities are additive. Thus when the target gas and cross-sensitive gas are present, the sensor reading will combine both concentrations to provide a summed reading on the detector
| XCell CO Sensors | |||||
| Scenario | Gas in Environment | Environmental Gas Concentration (ppm) | CO Cross-Sensitivity | Gas Detector CO Reading (ppm) | Actual CO in Environment (ppm) |
| Target Gas Concentration | CO | 50 | 100% | 50 | 50 |
| Cross-Sensitive Gas in Environment | NO | 50 | 84% | 42 | 0 |
| Target Gas & Cross-Sensitive Gas in Environment | CO/NO | 50 CO/50 NO | 100% CO/ 84% NO | 50 + 42 = 92 | 50 |
| Negative Cross-Sensitive Gas in Environment | HCN | 20 | –5% | –1 | 0 |
| Target Gas & Cross-Sensitive Gas in Environment | CO/HCN | 50 CO/20 HCN | 100% CO/–5% HCN | 50 + (–1) = 49 | 50 |
MSA XCell® Sensor Cross-Sensitivity Data*
| XCell CO & CO-HC Sensors | |||
| Gas Applied | Concentration Applied (ppm) | CO Cross-Sensitivity | CO Reading** |
| CO | 100 | 100% | 100 |
| H2S | 40 | 0% | 0 |
| SO2 | 9 | -4% | -1 |
| NO2 | 11 | 0% | 0 |
| NH3 | 25 | 0% | 0 |
| Cl2 | 10 | 0% | 0 |
| NO | 50 | 84% | 42 |
| HCN | 30 | -5% | -2 |
| Toluene | 53 | 0% | 0 |
| Isopropanol | 100 | -8% | -8 |
| H2 | 100 | 48% | 48 |
| XCell H₂S & H₂S-LC Sensors | |||
| Gas Applied | Concentration Applied (ppm) | H₂S Cross-Sensitivity | H2S Reading** |
| H2S | 40 | 100% | 40 |
| CO | 100 | 1% | 1 |
| SO2 | 9 | 14% | 2 |
| NO2 | 11 | -1% | -1 |
| NH3 | 25 | -1% | -1 |
| Cl2 | 10 | -14% | -2 |
| NO | 50 | 25% | 13 |
| HCN | 30 | -3% | -1 |
| Toluene | 53 | 0% | 0 |
| Isopropanol | 100 | -3% | -3 |
| H2 | 100 | 0% | 0 |
| XCell SO₂ (Single) Sensors | |||
| Gas Applied | Concentration Applied (ppm) | SO₂ (Single) Cross-Sensitivity | SO₂ Reading** |
| SO₂ | 24.5 | 100% | 25 |
| CO | 1000 | 0.0% | 0 |
| H2S | 199 | 0.1% | 1 |
| NO2 | 10 | -80% | -8 |
| NH3 | 121 | -0.1% | -1 |
| Cl2 | 15.3 | 0.7% | 1 |
| PH₃ | 5 | 18% | 1 |
| HCN | 50.4 | 5% | 3 |
| Isopropanol | 500 | 0% | 0 |
| H₂ | 2000 | 1% | 20 |
| Acetylene | 100 | 4% | 4 |
| XCell SO₂ (Two-Tox) Sensors | |||
| Gas Applied | Concentration Applied (ppm) | SO₂ Cross-Sensitivity | SO₂ Reading** |
| H2S | 40 | 100% | 40 |
| CO | 100 | 1% | 1 |
| SO2 | 9 | 14% | 2 |
| NO2 | 11 | -1% | -1 |
| NH3 | 25 | -1% | -1 |
| Cl2 | 10 | -14% | -2 |
| NO | 50 | 25% | 13 |
| HCN | 30 | -3% | -1 |
| Toluene | 53 | 0% | 0 |
| Isopropanol | 100 | -3% | -3 |
| H2 | 100 | 0% | 0 |
| XCell CO H₂-RES Sensors | |||
| Gas Applied | Concentration Applied (ppm) | CO H₂-RES
Cross-Sensitivity |
CO Reading** |
| CO | 100 | 100% | 100 |
| H₂S | 40 | 0% | 0 |
| SO₂ | 9 | –4% | –1 |
| NO₂ | 11 | 0% | 0 |
| NH₃ | 25 | 0% | 0 |
| Cl₂ | 10 | 0% | 0 |
| NO | 50 | 130% | 65 |
| HCN | 30 | –5% | –2 |
| Toluene | 53 | 0% | 0 |
| Isopropanol | 100 | –8% | –8 |
| H₂ | 100 | 5% | 5 |
| XCell NO₂ Sensors | |||
| Gas Applied | Concentration Applied (ppm) | NO₂ Cross-Sensitivity | NO₂ Reading** |
| NO₂ | 10 | 100% | 10 |
| CO | 60 | 3.3% | 2 |
| SO₂ | 10 | –86% | –9 |
| H₂S | 20 | –271% | –55 |
| NH₃ | 25 | 0% | 0 |
| O₃ | 1 | 100% | 1 |
| HCN | 4.7 | 2% | 1 |
| Acetylene | 100 | –1% | –1 |
| H₂ | 1000 | –0.1% | –1 |
| NO | 50 | 3% | 2 |
| H2 | 100 | 0% | 0 |
| XCell NH₃ Sensors | |||
| Gas Applied | Concentration Applied (ppm) | CO H₂-RES
Cross-Sensitivity |
CO Reading** |
| NH₃ | 25 | 100% | 25 |
| CO | 45 | 0% | 0 |
| H₂S | 20 | 75% | 15 |
| SO₂ | 10 | –39% | –4 |
| NO₂ | 2 | –74% | –2 |
| H₂ | 1000 | 0% | 0 |
| XCell NO₂ Sensors | |||
| Gas Applied | Concentration Applied (ppm) | NO₂ Cross-Sensitivity | NO₂ Reading** |
| Cl₂ | 10 | 100% | 10 |
| CO | 45 | 0% | 0 |
| H₂S | 20 | –0.7% | –1 |
| SO₂ | 10 | –34% | –4 |
| NO₂ | 2 | 19% | 1 |
| H₂ | 1000 | 0% | 0 |
- These cross-sensitivity values are intended for reference only and may change under varying environmental conditions, varying concentrations, varying sensor lots, and varying sensor age. These tables do not contain a complete or inclusive list of cross-sensitive gases, but rather is a sampling of the most common examples.
- All values have been rounded up to the nearest 1 ppm
- Transient effect
Cross-Sensitivity Data (Non-XCell Exotic Sensors)
| NO₂ Sensors | |||
| Gas Applied | Concentration Applied (ppm) | NO₂ Cross-Sensitivity | NO₂ Reading** |
| CO | 300 | 0% | 0 |
| H₂S | 15 | –8% | –2 |
| SO₂ | 5 | 0% | 0 |
| NO | 35 | 0% | 0 |
| Cl₂ | 1 | 100% | 1 |
| ClO₂ Sensors | |||
| Gas Applied | Concentration Applied (ppm) | ClO₂ Cross-Sensitivity | ClO₂ Reading** |
| Alcohols | 1000 | 0% | 0 |
| CO | 100 | 0% | 0 |
| Cl₂ | 1 | 60% | 1 |
| O₃ | 0.25 | 280% | 1 |
| H₂ | 3000 | 0% | 0 |
| H₂S | 20 | –25% | –5 |
| PH₃ Sensors | |||
| Gas Applied | Concentration Applied (ppm) | PH₃ Cross-Sensitivity | PH₃ Reading** |
| AsH₃ | 0.15 | 67% | 1 |
| SiH₄ | 1 | 90% | 1 |
| B₂H₆ | 0.3 | 35% | 1 |
| GeH₄ | 0.6 | 92% | 1 |
| SO₂ | 5 | 20% | 1 |
| H₂ | 1000 | 0.1% | 1 |
| C₂H₄ | 100 | 1% | 1 |
| CO | 1000 | 0.1% | 1 |
| HCN Sensors | |||
| Gas Applied | Concentration Applied (ppm) | HCN Cross-Sensitivity | HCN Reading** |
| H₂S | 20 | 300% | 60 |
| NO₂ | 10 | –180% | –18 |
| Cl₂ | 10 | 12% | 2 |
| NO | 50 | 1% | 1 |
| SO₂ | 20 | 10% | 2 |
| CO | 400 | 0.1% | 1 |
| H₂ | 400 | 0.1% | 1 |
| C₂H₄ | 80 | 0.1% | 1 |
| NH₃ | 20 | 1% | 1 |
| CO₂ | 50000 | 0.1% | 50 |
| NO Sensors | |||
| Gas Applied | Concentration Applied (ppm) | NO Cross-Sensitivity | NO Reading** |
| CO | 300 | 0% | 0 |
| SO₂ | 5 | 0% | 0 |
| NO₂ | 5 | 30% | 2 |
| H₂S | 15 | 10% | 2 |
- These cross-sensitivity values are intended for reference only and may change under varying environmental conditions, varying concentrations, varying sensor lots, and varying sensor age. These tables do not contain a complete or inclusive list of cross-sensitive gases, but rather is a sampling of the most common examples.
- All values have been rounded up to the nearest 1 ppm
Note: This Bulletin contains only a general description of the products shown. While product uses and performance capabilities are generally described, the products shall not, under any circumstances, be used by untrained or unqualified individuals. The products shall not be used until the product instructions/user manual, which contains detailed information concerning the proper use and care of the products, including any warnings or cautions, have been thoroughly read and understood. Specifications are subject to change without prior notice. MSA is a registered trademark of MSA Technology, LLC in the US, Europe, and other Countries. For all other trademarks visit https://us.msasafety.com/Trademarks.
MSA operates in over 40 countries worldwide. To find an MSA office near you, please visit MSAsafety.com/offices.
0800-177-MC / 06.2024
© MSA 2024
FAQ
Q: Are the cross-sensitivity values fixed?
A: Cross-sensitivity values are intended for reference only and may change under varying environmental conditions, concentrations, sensor lots, and sensor age.
Q: Is the provided list of cross-sensitive gases exhaustive?
A: No, the tables do not contain a complete list but offer common examples of cross-sensitive gases.
Documents / Resources
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MSA 0800-177-MC Gas Detectors and Altair [pdf] Instruction Manual 2X, 4XR, 5X, 0800-177-MC Gas Detectors and Altair, 0800-177-MC, Gas Detectors and Altair, Detectors and Altair, and Altair |