Correlating Triton ICP-OES test to Hanna Ultra Low Range Phosphorus

[WallysWorld]

I'd like to try to correlate the results that I received from the Triton ICP-OES test against the test I do at home with my Hanna Ultra Low Range Phosphorus HI736 tester.

I took the water sample for Triton at the same time as the water I tested with Hanna.

My Hanna result was 34 ppb
The Triton results are P - 7.009 µg/l; PO4 - 0.02144754 mg/l

Not completely certain how to compare these different tests and the results. I'm not worried about them being equal, I'm certain that there is some level of uncertainty with both tests. Any assistance would be appreciated.

As a side note does anyone know the measurement uncertainty that Triton has for their tests?

 

[Randy Holmes-Farley]

The 7 and the 34 are comparable units. They do not measure exactly the same things. Triton will detect all forms of P including organics. Hanna is phosphate only. Of course, that can’t explain why the Hanna is higher. I don’t know which, if either, is accurate.

 

[WallysWorld]

The 7 and the 34 are comparable units. They do not measure exactly the same things. Triton will detect all forms of P including organics. Hanna is phosphate only. Of course, that can’t explain why the Hanna is higher. I don’t know which, if either, is accurate.

So if I use the formula supplied from Hanna to convert phosphorus(P) to phosphate(PO4), (P * 3.066) / 1000, the Triton P measurement and PO4 are essentially the same number. Is this a correct conversion?

I'm not certain how to ***** the difference either. The accuracy spec on the Hanna is +5 ppb * 5% of rdg, so given the reading of 34 ppb, the true value could be 27.3 to 40.7. I don't know what the uncertainty spec is on the Triton results, but I think that its better than the Hanna error. I may just have to live with very large uncertainties....the state of the art in measurement of this parameter probably isn't that good.

 

[MnFish1]

I'd like to try to correlate the results that I received from the Triton ICP-OES test against the test I do at home with my Hanna Ultra Low Range Phosphorus HI736 tester.

I took the water sample for Triton at the same time as the water I tested with Hanna.

My Hanna result was 34 ppb
The Triton results are P - 7.009 µg/l; PO4 - 0.02144754 mg/l

Not completely certain how to compare these different tests and the results. I'm not worried about them being equal, I'm certain that there is some level of uncertainty with both tests. Any assistance would be appreciated.

As a side note does anyone know the measurement uncertainty that Triton has for their tests?

Your PO4 is 21.44754 ppb. your P is 0.007 ppm so divide by 1000 to get ppb. (from the triton results) @Randy Holmes-Farley can check this