
Private customers can also find our range in our partner store Ampha-Analyse.
The pH range 8-12 covers the alkaline to strongly alkaline range that must be monitored in numerous industrial applications. Boiler water, cooling water with inhibitors and alkaline cleaning solutions are typically in this pH range.
In boiler technology, the feed water is often set to pH 9-10 to minimize corrosion. Monitoring is essential, as both too low and too high pH values can cause damage to the system.
In wastewater treatment, alkaline wastewater must be neutralized before discharge. The pH limit value for discharges is pH 6.5-9.5.
The CALDUR® pH 8-12 Test Set – Colorimetric uses a mixing indicator that takes on a characteristic color depending on the pH value of the sample. After adding a reagent to the water sample, the color is compared with the supplied color chart within 1 minute.
Higher resolution in the alkaline range than universal pH test sets
Very economical for continuous use
Immediate results on site
Particularly quick and easy handling
Safe transportation and protection of reagents
The sample should have a temperature between 15 and 25°C, as the pH value is temperature-dependent. If the boiler water is hot, allow the sample to cool down to room temperature before measuring. CO₂ losses during cooling can increase the pH value.
| Measuring level | Description |
|---|---|
| pH 8.0 | Slightly alkaline (blue-green) |
| pH 8.5 | Alkaline (blue) |
| pH 9.0 | Moderately alkaline (strong blue) |
| pH 10.0 | Strongly alkaline (blue-violet) |
| pH 11.0 | Very strongly alkaline (violet) |
| pH 12.0 | Extremely alkaline (dark violet) |
With a CALDUR® pH 8-12 test set you can carry out 300 measurements.
This refers to the quantity of reagents contained.
Readability: ± 0.5 pH units
Reproducibility: Very good if the application instructions are followed
Interference: Heavily colored or true samples can make color readings difficult. The Reagent may deviate slightly at very high salt concentrations. Strong reducing agents can influence the Reagent.
The sample is extremely alkaline. Dilute the sample 1:10 with distilled water and measure again. The actual pH value is then correspondingly higher than the value read.
Use the CALDUR® pH 5-8 test set for the neutral range.
Reagents (1 reagent)
| Property | Value |
|---|---|
| Parameters | pH value (basic) |
| Item number | 31-072390 |
| Method | Colorimetric (mixing indicator) |
| Measuring principle | Color comparison with 6-stage color chart |
| Measuring range | pH 8 to 12 |
| Color scale | 6 measuring levels (8.0 / 8.5 / 9.0 / 10.0 / 11.0 / 12.0) |
| Analysis duration | 1 minute |
| Number of provisions | 300 |
| Number of reagents | 1 |
| Packaging | Hinged lid box |
| Packaging size | 103 x 91 x 36 mm |
| weight | approx. 120 g |
| Scope of delivery |
|---|
| 1 reagent bottle (mixing indicator) 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 |
|---|---|---|---|
| Mixing indicator (pH 8-12) | 30 ml | 24 months (24M) | Indicator 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.
| Packaging | Hinged lid box, Refill pack |
|---|


