Is Test Equipment Accuracy an Illusion?
Is Test Equipment Accuracy an Illusion?
October 24th, 2008
On a regular basis I’m asked the question; “How accurate is this moisture balance?”
The questioner asks for the answer in terms of percent moisture. When I answer “ it depends”, I always get the unspoken response. “Why did I ask this stupid idiot?”
The detailed answer is complicated because the questioners want to know accuracy in terms of a percentage (%). This is a relative rather than an absolute measurement term. In the case of a Loss on Drying (LOD) moisture instrument it depends on the size of the sample.
The detailed answer can be understood with this example of using the LOD method. The percent moisture (%) is calculated buy subtracting the weight of sample at the end of the test from the weight of sample at the beginning of the test. We call that the difference. The last part of the calculations is to divide this difference by the beginning weight..
To read the entire article please go to the CSC Scientific blog by clicking on the link below:
Is Test Equipment Accuracy an Illusion?
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Which is more accurate to measure a KOH solution (40-50% w/w with silicates) titration or use of refractometer? I once compared the concentartion values using fresh 45% KOH and are both statistically equal, however, after using it (spent KOH already with silicates) i obtained titration data 2 unit lower than refractometer reading.