Description
Hydrogen Sulphide (H2S) gas is often referred to as sewer gas, stink damp, or sour gas, is a colourless, highly toxic, flammable gas. It’s well-known for its characteristic rotten egg smell, though it’s important to note that at higher concentrations, H2S rapidly deadens the sense of smell, making it an unreliable indicator of its presence. It is produced naturally through the anaerobic decomposition of organic matter (without oxygen) by bacteria. It’s also a by product of various industrial processes. Therefore, it can be found in numerous settings where people work or are present.
Key Properties
- Colourless: Invisible to the naked eye
- Highly Toxic: Even at low concentrations, it can be fatal
- Flammable/Explosive: Can ignite and form explosive mixtures with air
- Heavier than Air: Tends to accumulate in low-lying areas, confined spaces, and trenches
Replacement Sensor, Part No. 17124975-2, Properties
| Gas Detected (Abbreviation) |
Sensor Type | Measurement | Response time (Seconds) |
Calibration Gas & Concentration |
||
|---|---|---|---|---|---|---|
| Range | Resolution | T50 | T90 | |||
| Hydrogen Sulphide H2S |
Electrochemical | 0 to 500 ppm | 0.10 ppm | 7 | 20 | H2S 25 ppm |
Toxic Gas Sensor Cross-sensitivity Table
| Target Gas | Sensor | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CO | CO (H2 Low) |
H2S | SO2 | NO2 | Cl2 | ClO2 | HCN | HCl | PH3 | NO | H2 | NH3 | |
| CO | 100 | 100 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 20 | 0 |
| H2S | 5 | 5 | 100 | 1 | -40 | -3 | -25 | 10 | 300 | 25 | 10 | 20 | 25 |
| SO2 | 0 | 5 | 5 | 100 | 0 | 0 | 0 | – | 40 | – | 0 | 0 | -40 |
| NO2 | -5 | 5 | -25 | -165 | 100 | 45 | – | -70 | – | – | 30 | 0 | -10 |
| Cl2 | -10 | 0 | -20 | -25 | 10 | 100 | 60 | -20 | 6 | -20 | 0 | 0 | -50 |
| ClO2 | – | – | – | – | 20 | 100 | – | – | – | – | – | – | – |
| HCN | 15 | – | – | 50 | 1 | 0 | 0 | 100 | 35 | 1 | 0 | 30 | 5 |
| HCl | 3 | – | – | 5 | 0 | 2 | 0 | 0 | 100 | 0 | 15 | 0 | 0 |
| PH3 | – | – | – | – | – | – | -100 | 425 | 300 | 100 | – | – | – |
| NO | 25 | 40 | -0.2 | 1 | 5 | – | – | -5 | – | – | 100 | 30 | 0 |
| H2 | 22 | 3 | 0.08 | 0.5 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 100 | 0 |
| NH3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 100 |
The table above reflects the percentage response provided by the sensor (top row) when exposed to a known concentration of the target gas (column 1).
The numbers were measured under these environmental conditions: 20 °C (68 °F), 50% RH and 1 atm.
The specified cross-interference numbers apply to new sensors only and may vary with time as well as from sensor to sensor.
“-” means no data available.
This table is given as a reference only and is subject to change.
A combined CO/H2S cell is also available for the MX6 gas detector and this sensor can be found on the link below
