I would like to obtain some additional information regarding your PALM ABBE PA202X-011-014 ethylene glycol refractometer. Our enquiry is related to the use of the refractometer for measuring runoff and surface waters for ethylene glycol. Specific questions are:
1. Units of measure. Does the instrument have the capability of reporting measurements in mg/L?
mg/L is a tough number to display on the refractometer. Refractometers typically measure in the parts per thousand range. Mg/L is parts per million. This is well beyond the detection threshold of most handheld refractometers.
2. What is the range (lower detection limit and upper limit) of detection of the instrument in mg/L?
0 to 1,000,000 mg/L Theoretical.
3. If there is an upper range, is there a procedure specified for sample dilution?
Upper range would be 100% EG. No dilution would be necessary.
4. Are there any properties of the matrix (water) that may interfere with the analyses (e.g., suspended solids, dissolved solids, pH)?
Dissolved solids are additive to refractive index. Any dissolved solids besides EG would cause an error in the reading. Most suspended solids should have no effect on the readings.
5. What is the precision and accuracy of the measurements (+/- in terms of mg/L)? Does the accuracy/precision vary according to sample concentration?
The average full scale precision would be approximately +/- 1.500 mg/L. and Yes. It is approximately +/- 1.395 at the bottom of the scale and +/- 3.966 at 100% EG.