CALDUR® Sulfide – Photometric
Determination of sulphide in water by photometer (0.05-1.0 mg/l S²-)

Private customers can also find our range in our partner store Ampha-Analyse.
Reagent for CALDUR® Sulfide – Photometric:
See also:
CALDUR® Sulfide Test Set – Photometric
What is sulfide measured for?
Sulphide (S²-) is produced by the anaerobic decomposition of organic substances containing sulphur and can cause an unpleasant smell of rotten eggs as hydrogen sulphide (H₂S). Even low concentrations are corrosive and can damage pipelines and structures.
Sulphide is harmful to health in higher concentrations and can cause respiratory and eye irritation in people who work with contaminated water. Sulphide is undesirable in drinking water treatment and must be reliably detected.
In industrial water treatment, in sewage treatment plants and in groundwater samples, sulphide control is essential to prevent corrosion and ensure water quality.
How does the test set work?
The CALDUR® Sulfide Test Set – Photometric is based on the DPD method. After adding two reagents to the water sample, a characteristic coloration develops within 7 minutes, the concentration of which is precisely determined with the WINLAB Data Line photometer.
Advantages of the CALDUR® test set
- Sensitive measuring range 0.05 – 1.0 mg/l S²-
Detection of even low sulphide concentrations
- 100 provisions per set
Economical for regular checks
- High precision due to photometric evaluation
Objective, reproducible measurement results with the WINLAB Data Line
- Proven DPD method
Reliable results even with stained samples
Areas of application
Carrying out the measurement:
- Fill the round cuvette with sample up to the 10 ml mark
- Add 5 drops of reagent A and mix
- Add 3 drops of reagent B and mix
- Wait for 7 minutes reaction time
- Insert the cuvette into the WINLAB Data Line photometer
- Start measurement – result is displayed directly in mg/l S²-
Tip for best results
The sample should be measured immediately after collection, as sulphide forms volatile hydrogen sulphide (H₂S). Do not shake or aerate the sample in order to avoid sulphide losses.
If H₂S can be detected by smell (from approx. 0.05 mg/l), a measurement is strongly recommended.
Important notes
- Do not aerate or shake the sample – sulphide volatilizes as H₂S
- Adhere exactly to the reaction time of 7 minutes
- Avoid direct sunlight during the measurement
- Wipe the cuvette with a lint-free cloth before measuring
- Thoroughly rinse the test tube with the sample before each measurement
- H₂S is toxic – work in a fume cupboard at high concentrations
Measuring range
| Property | Value |
|---|---|
| Measuring range | 0.05 to 1.0 mg/l S²- |
| Resolution | 0.01 mg/l |
| Method | DPD method, photometric evaluation |
In contrast to the colorimetric method (color chart), the photometer provides exact numerical values with a higher resolution. Intermediate values are calculated automatically – ideal for documentation and quality assurance.
Number of possible destinations
You can carry out 100 measurements with one CALDUR® Test Set Sulfide.
This refers to the quantity of reagents contained.
Measuring accuracy and reproducibility
Resolution: 0.01 mg/l
Reproducibility: Very good if the application instructions are followed
Interference: Strongly reducing substances can influence the result. Compared to the colorimetric method, the photometric measurement is less susceptible to lightly stained samples, as the wavelength selectivity of the photometer better compensates for interfering background staining.
What to do if measured values are out of range?
Measured value > 1.0 mg/l
| Verduction | Execution | Calculation of the measured value |
|---|---|---|
| 1:1 | 5 ml sample + 5 ml sulfide-free water | Measured value × 2 |
| 1:4 | 2 ml sample + 8 ml sulfide-free water | Measured value × 5 |
Measured value < 0.05 mg/l
Measured value is below the detection limit. For more sensitive measurements, please contact our technical support.
Specifications at a glance
| Property | Value |
|---|---|
| Parameters | Sulphide (S²- / H₂S) |
| Item number | 31-073542 |
| Method | Photometric (DPD) |
| Measuring principle | Photometric evaluation with WINLAB Data Line |
| Measuring range | 0.05 to 1.0 mg/l S²- |
| Resolution | 0.01 mg/l |
| Duration of analysis | 7 minutes |
| Number of provisions | 100 |
| Number of reagents | 2 |
| Packaging | Plastic bag |
| Scope of delivery |
|---|
| 2 reagent bottles (reagent A, reagent B) with detailed labeling |
| 1 round cuvette (10 ml) |
| Detailed operating instructions (DE/EN) |
| Safety data sheets for all reagents |
| Resealable plastic bag |
Reagent details
| Reagent | Volume | Shelf life | Notes |
|---|---|---|---|
| Reagent A (DPD 1) | 30 ml | 24 months (24M) | DPD reagent, shake before use |
| Reagent B (buffer) | 10 ml | 24 months (24M) | Buffer solution, shake before use |
Shelf life: The shelf life starts from the date of manufacture (printed on the bottle).
After opening, the reagents should be used within 12 months.
Store the test kit in a dry, cool place (10-25°C) and protected from direct sunlight.
Required accessories
The photometer is not included in the test set and is available separately.
Additional information
| Packaging | Plastic bag, Refill pack |
|---|---|
| Product category | Testset |
Flyer
Operating instructions
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