
Private customers can also find our range in our partner store Ampha-Analyse.
Iron is a naturally occurring element that can be found in almost all bodies of water and groundwater sources. Although iron is essential for the human body, too high a concentration in drinking water can lead to undesirable effects. Elevated iron levels cause a brownish discoloration of the water, a metallic taste and can lead to deposits in pipes and household appliances.
The limit value for drinking water in Germany is 0.2 mg/l (Drinking Water Ordinance). The CALDUR® Iron LRS test set is specially designed for the highly sensitive measurement of very low iron concentrations. With a detection limit of just 0.01 mg/l, it is ideal for monitoring drinking water, ultrapure water and applications where even the smallest traces of iron need to be detected.
Iron can enter the water from various sources: natural leaching from iron-containing rock layers, corrosion of iron pipes, industrial discharges or through iron-containing additives in water treatment. Precise monitoring of extremely low iron concentrations is particularly important in drinking water treatment, in the food industry and in sensitive processes.
The CALDUR® Iron LRS Test Set – Colorimetric works according to the proven ferrozine method with optimized sensitivity. Ferrozine forms an intense violet color complex with iron(II) ions, the intensity of which is proportional to the iron concentration. The special reagent formulation enables the detection of iron concentrations as low as 0.01 mg/l.
After a reaction time of 5 minutes, the measured value is determined by direct color comparison with a supplied 6-stage color chart. This colorimetric method enables fast and reliable on-site determination without the need for expensive laboratory equipment.
Ideal for drinking water, ultrapure water and sensitive processes
Ideal for on-site use – saves time and enables immediate decisions
Cost-efficient for regular inspections in waterworks and industry
Fewer work steps for faster results
Flexible for simple on-site tests or precise laboratory analyses with photometer
Safe transportation and protection of reagents – durable and reliable
For best results, the water sample should be clear and free of suspended solids.
If the water is cloudy, pre-filtration with a filter paper (e.g. Whatman No. 1) is recommended.
Use particularly clean glassware for trace analysis.
| Measuring level | Description |
|---|---|
| 0.01 mg/l | Trace concentration (barely visible violet) |
| 0.03 mg/l | Very low concentration (slightly violet) |
| 0.06 mg/l | Low concentration (light violet) |
| 0.1 mg/l | Slightly increased concentration (violet) |
| 0.2 mg/l | Drinking water limit value range (clearly violet) |
| 0.5 mg/l | Increased concentration (intense violet) |
You can carry out 100 measurements with one CALDUR® Iron LRS test set.
This refers to the quantity of reagents contained.
Readability: ± 1 color level
Reproducibility: Very good if the application instructions are followed
Interferences: Turbidity and coloration of the sample can influence the result (filter the sample if necessary).
For concentrations above 0.5 mg/l, we recommend the CALDUR® Iron LR test set (measuring range 0.05-1.0 mg/l) or the Iron HRS test set (measuring range 0.2-10 mg/l) for even higher concentrations.
Measured value is below the detection limit. This is generally not critical and indicates
that the iron concentration is extremely low (water is harmless with regard to iron).
Reagent (ferrozine)
| Property | Value |
|---|---|
| Parameters | Iron (Fe) – Low Range Sensitive |
| Item number | 31-072307 |
| Method | Colorimetric (ferrozine) |
| Measuring principle | Color comparison with 6-stage color chart |
| Measuring range | 0.01 to 0.5 mg/l Fe |
| Color scale | 6 measuring levels (0.01 / 0.03 / 0.06 / 0.1 / 0.2 / 0.5 mg/l) |
| Duration of analysis | 5 minutes |
| Number of provisions | 100 |
| Number of reagents | 1 (ferrozine reagent) |
| Packaging | Hinged lid box |
| Packaging size | 103 x 91 x 36 mm |
| weight | approx. 150 g |
| Scope of delivery |
|---|
| 1 reagent bottle (iron LRS reagent) with detailed labeling |
| 1 test tube with 10 ml scale |
| 1 color card with 6 measuring levels |
| Detailed operating instructions (DE/EN) |
| Safety data sheets for all reagents |
| Robust hinged lid box (103 x 91 x 36 mm) |
| Reagent | Volume | Shelf life | Notes |
|---|---|---|---|
| Iron LRS Reagent | 25 ml | 48 months (48M) | Ferrozine 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 away from direct sunlight.
| Packaging | Hinged lid box, Refill pack |
|---|


