Siemens Water Technologies Introduces Total-Check 900 In-Line TOC Monitor For Laboratory Applications
Warrendale - Siemens Water Technologies has introduced the stand-alone Total-check 900 in-line TOC monitor. The monitor can be connected to any high-purity water laboratory system to provide an accurate measurement of product water TOC (total organic carbon) levels from 1 to 999 ppb (parts per billion) with repeatability of ±5% and accuracy of ±1 ppb. Available in North America and Europe, it is designed for laboratory personnel who need to measure the TOC in high-purity water produced by systems that do not feature a built-in monitor.
For critical applications in the clinical, analytical or municipal laboratory, it is essential to monitor organic impurities, measured as the TOC, in high-purity water produced by a laboratory water polishing system. TOC is a measure of the concentration in aqueous solutions of carbon from oxidizable organic compounds. Measuring the TOC will give a clear picture of the water quality produced. Even low TOC levels of less than 50 parts per billion (ppb) can negatively affect some laboratory experiments.
Three operating modes are easily accessed with the push of a button: the automatic analysis mode gives a continuous sample analysis and displays each stage of the cycle; the manual analysis mode prevents repeated analysis of a stagnant sample; the standby mode prevents sample water from flowing through the monitor.
Other benefits of the Total-check 900 monitor include fast, easy installation; easy to read single-line LCD display; and the ability to be wall mounted.
The Total-check 900 monitor measures levels of TOC in purified water to help laboratories meet or comply with guidelines specified in internationally recognized U.S. standards organizations such as ASTM (American Society for Testing and Materials), USP (U.S. Pharmacopoeia), CLSI (Clinical and Laboratory Standards Institute) or CLRW (Clinical Laboratory Reagent Water). The monitor can be re-calibrated upon the user's request, and has been designed to take into account the suitability test requirements as specified in USP 643.
The principles of TOC measurement are as follows: A water sample is introduced into the TOC monitor sensor cell, and the temperature and resistivity are measured to obtain a reference value. This value is stored in the TOC monitor's memory bank. Organic compounds in the water sample are oxidized for a predetermined period with ultraviolet oxidation. The resistivity and temperature of the oxidized sample are then measured and compared to the reference value. A proprietary algorithm is applied to the differential values of the reference sample and oxidized sample to determine the TOC of the water sample. The results are reported in parts per billion (ppb) and displayed on the LCD monitor.
SOURCE: Evoqua Water Technologies