Test results of the effect of potassium chloride content on the determination of MAP content in accordance with ISO 7202 (n = 3, P = 0_95)
| Lp. | Quantity KCl/g | Quality certificate % MAP | Found MAP [%] |
|---|---|---|---|
| 1 | 10 | 99.60 | 99.79 ± 0.15 |
| 2 | 12 | 99.63 ± 0.17 | |
| 3 | 14 | 99.56 ± 0.19 | |
| 4 | 16 | 99.99 ± 0.17 | |
| 5 | 18 | 99.92 ± 0.15 | |
| 6 | 20 | 99.97 ± 0.16 |
Normative conditions according to the requirements of ISO 7202:2018 and proposals for modification of some procedures for determining the MAP content
| Action | Current text of ISO 7202:2018 (p. 13.10) | Proposed modification of the procedure |
|---|---|---|
| Sample preparation | The beaker capacity is determined to be 600 ml | Also determine the maximum diameter of the beaker (70 mm) |
| Cover the sample with a watch glass while heating | Cover the sample with a watch glass after adding acetone and DW, as well as during heating | |
| Mixing the sample with acetone for no less than 10 min | Also determine the maximum mixing time (10 to 12 min) | |
| Mixing the sample with WD for no less than 30 min | Also determine the maximum mixing time (30 to 35 min) | |
| Mixing the sample (mixing speed not specified) | Also determine the maximum mixing speed (300 rpm) | |
| After the sample has cooled from 25 to 20° C, fill to the mark | After reaching the temperature of 20±2° C, fill to the mark | |
| Titration | Add 20 g KCl and 20 ml WD | Add 10 to 12 g KCl and 5 to 10 ml DW |
| Mixing the sample (mixing speed not specified) | Also determine the maximum mixing speed (300 rpm) | |
| Titrate to pH 7.2 to 7.7 | Titrate to pH 7.85 to 7.90 |
Technical parameters of regenerated ABC extinguishing powders (average of three repetitions) in accordance with the PN-EN 615 standard
| Sample No. | Bulk density (g/ml) | Resistance to caking | Resistance to water wetting | Fire test performance | Moisture (%) | Sieve analysis (%) | ||
|---|---|---|---|---|---|---|---|---|
| > 125 μm | > 63μm | > 40μm | ||||||
| 1 | 0.91 | yes | yes | yes | 0.11 | 13.7 | 41.1 | 64.8 |
| 2 | 0.94 | yes | yes | yes | 0.14 | 13.4 | 45.4 | 62.9 |
| 3 | 0.92 | yes | yes | yes | 0.10 | 12.1 | 39.2 | 60.9 |
| 4 | 0.89 | yes | yes | yes | 0.17 | 14.0 | 41.4 | 64.8 |
Comparison of MAP content test results for ABC NTL30 fire-extinguishing powder samples using the titrimetric method and the spectrophotometric method (n = 3, P = 0_95)
| Sample No. | UV-VIS method | Reference method |
|---|---|---|
| MAP content in fire-extinguishing powder samples, % | ||
| 1 | 32.11 ± 0.04 | 31.72 ± 0.26 |
| 2 | 33.50 ± 0.09 | 33.20 ± 0.16 |
| 3 | 33.77 ± 0.08 | 34.02 ± 0.12 |
| 4 | 33.44 ± 0.10 | 33.85 ± 0.12 |
| mixture of patterns (MAP – 32.00%) | 31.96 ± 0.09 | 32.25 ± 0.14 |
Comparison of the sequence of operations and time of MAP content determination using the reference method vs_ the spectrophotometric method
| Action | Titration method | UV-VIS method |
|---|---|---|
| Time (min) | ||
| Weighing the sample | 1 | 2 |
| Adding reagents | 1 | 1 |
| Mixing without heating | 40 | - |
| Heating | 25 | 5 |
| Filtering | 20 | 5 |
| Cooling | 25 | - |
| Preparing for analysis | 7 | 23 |
| Taking the sample | 1 | - |
| Titration | 5 | - |
| Absorbance measurement | - | 1 |
| Sum | 125 | 37 |