How accurate and reliable are test strips?
Test strips can be quite accurate. Most manufacturers utilize several industry-standard reference methods to compare and calibrate their strips. One of the most comprehensive collections of reference methods is contained in the AWWA manual for water and wastewater treatment and evaluation. Once the standard reference method is established, the test strip manufacturer determines the level of accuracy that the strips should meet; generally the accuracy is within a color block up to the expiration date of the strip. The test strip is put through multiple testing phases and scenarios in order to see how it performs in real-world situations. After the grueling testing phase, the data is collected and the results are evaluated. If the test strip meets the desired level of performance, it is accepted and ready to be sold. Competent test strip manufacturers will not release a test strip if its performance does not meet the highest possible accuracy and reliability.
