H2S sensor
Hydrogen sulfide
Reliable real-time
information on H2S
SENSOR-BASED | BEST AVAILABLE ACCURACY
Where is it found?
Most of this gas in the atmosphere has a natural origin from organic matter decomposition. Anthropically, it occurs in processes involving sulphur compounds and organic matter at high temperatures.
Some industrial activities that emit this gas are paper pulp manufacturing, oil refining, water treatment plants and the viscose manufacturing textile industry.
Why is it harmful?
Hydrogen Sulfide (H2S) affects mainly the respiratory system with the first symptoms being nose, throat and eye irritation.
This compound begins to be detected by human smell at concentrations much lower than those that can harm health. Short-term exposures to high concentrations can cause headaches, dizziness and vomiting.
H2S cartridge
The H2S cartridge has a built-in electrochemical sensor very sensitive to its target pollutant allowing it to detect small changes in H2S concentration. This cartridge also responds to methyl mercaptan (CH4S) and other total reduced sulphur compounds (TRS).
To cover different applications, there are 2 measurement ranges:
- Type A: detects low ppb concentrations in real environments. Although the Kunak algorithm corrects the temperature variations well, it is not recommended to use this cartridge to measure levels below 15 ppb.
- Type B: a higher range version that can measure up to 20 ppm, not so precise at low concentrations.
Technical specifications
mg/m3, ppm(B)
0 - 20 ppm(B)
0.01 ppm(B)
0.01 ppm(B)
0.01 ppm(B)
± 0.05 ppm(B)
-0.05 ppm ≤ a ≤ +0.05 ppm(B)
< 0.02 ppm(B)
- Measurement range: concentration range measured by the sensor.
- Resolution: smallest unit of measurement that can be indicated by the sensor.
- Operating temperature range: temperature interval at which the sensor is rated to operate safely and provide measurements. (**) In PM sensor Type A: -40 to 50ºC with heater (more information on this version on request).
- Operating RH range: humidity interval at which the sensor is rated to operate safely and provide measurements.
- Recommended RH range: Recommended relative humidity range for optimal sensor performance. Continuous exposure outside the recommended range may damage the cartridge.
- Operating life: time period during which the sensor can operate effectively and accurately under normal conditions.
- Guarantee range: concentration range covered by Kunak's guarantee.
- LOD (Limit Of Detection): measured at laboratory conditions at 20ºC and 50% RH. The limit of detection is the minimum concentration that can be detected as significantly different at zero gas concentration, calculated according to the Technical Specification CEN/TS 17660.
- Repeatability: measured at laboratory conditions at 20ºC and 50% RH. Closeness of the agreement between the results of successive measurements of the same measure carried out under the same conditions of measurement, calculated according to the Technical Specification CEN/TS 17660.
- Response time: time needed by the sensor to reach 90% of the final stable value.
- Typical precision - R2: statistics obtained between the device hourly measurements and reference instruments in field test between -10 to +30ºC at different locations. (*) For the type B PM sensor, the expected error for PM10 is higher in presence of coarse particles.
- Typical accuracy: for criteria pollutants is the average Mean Absolute Error (MAE) obtained between the device hourly measurements and reference instruments for 1 to 8 months field test between -10 to +30ºC in different countries. For other pollutants is the expected error of the measurement at the reading.
- DQO-Typical U(exp): Data Quality Objetive expresed as the Expanded Uncertainity in the Limit Value obtained between the device hourly measurements and reference instruments for 1 to 8 months field test between -10 to +30ºC in different countries, calculated according to the European Air Quality Directive 2024/2881 and from the Technical Specification CEN/TS 17660. (*) For the type B PM sensor, the expected error for PM10 is higher in presence of coarse particles.
- Typical intra-model variability: calculated as the standard deviation of the three sensor means in 1 to 8 months field test between -10 to +30ºC in different countries.
A, B, C, D superindex: the super indexes refer to different types of cartridges related to the same target pollutant but with different technical specifications.
