| Laboratory Test Comparisons
and Procedural Differences |
| Test Name |
DNR Test No. |
Closest Equiv. R&H Test No(s)
|
Comments |
| Electrical Conductivity |
C1A/3 |
3A1 |
R&H- Dry KCl for 2 hrs @ 1100C
DNR- Dry KCl for 2 hrs @ 1050C |
| pH 1:5 in H20 |
C2A/2 |
4A1 |
R&H- Specifies water with conductivity
<1.5 x 10-3 dS/m. DNR- Water quality not specified. |
| pH 1:5 in 0.01mol CaC12 |
C2B/2 |
4B2 |
R&H- Sample is mixed intermittently for
15 min after addition of CaC12 solution. DNR- Initial mix only. |
| pH in H2O2 |
C2C/1 |
4E1 |
No difference in procedures. |
| Lime Requirement |
C3A/3 |
16D1 |
R&H- Stand 4 days, re-mix twice/day. Measure
pH while stirring.
DNR- Stand 3 days, no further mixing. |
| CEC Ex. Cations |
C5A/4 |
15F3, 15F1, 15F2 |
R&H- Sr/Cs flaming solution for AAS DNR-
Na or K flaming solutions. Uses diluter/disperser for references & samples. |
| CEC Ex. Bases |
C5B/1 |
1514, 15C1 |
No differences in analysis of Ca/KNO3
extracts. R&H- Leaching x 4.
DNR- Mix & centrifuge x 3, and as per C5A/4. |
| Organic Carbon |
C6A/2 |
6B1 |
R&H- Heat to >1350C in
temp. controlled digester for 30 min. Measure residual Dichromate colour @ 600 nm, Sucrose
reference. DNR- Heat to >1350C for 1/2 min, cool slowly on asbestos mat.
Titrate residual Dichromate c. FeSO4 solution, K2Cr2O7
ref. |
| Bray Phosphorus |
C8A/3 |
9E1 |
DNR- Uses Diluter/Dispenser instead of
Pipettes and Volumetric Flasks for standards and subsamples. |
| Phosphorus Sorption |
C8B/2 |
9I1 |
As above. |
| Lactate Phosphorus |
C8C/1 |
9D1 |
No difference in procedures. |
| Extractable Iron |
C15A/1 |
13C1 |
No differences in procedures. |
DNR-- Department of Natural Resources methods.
Laboratory Comparisons and Procedural Differences