One priority for the CPCA Industrial Relations Committee (IRC) is to understand, educate and resolve frustrations around the topic of product certification. To this end the committee has undertaken several surveys among members, market and certification bodies.
This is the first of a series of articles that will highlight and inform readers on several aspects of product certification. Today’s article focuses on Factory Audits.
Chlorine is a strong oxidant used to disinfect drinking water, process wastewater and provide sanitation that is essential to protecting public health.
Utilizing Chlorine gas requires special storage, safety and handling considerations and is usually utilized in large municipalities. Hypochlorite solutions can be manufactured onsite, is safer to handle but may cost slightly more than utilizing chlorine gas. Chlorine is a member of the Halogen group of chemicals which include Bromine, Iodine and Ozone. These halogens are oxidizers and will interfere with the free chlorine readings picked up by the sensor and as such, a strong presence of these chemicals in solution could create false reading for the presence of Chlorine.
Nuclear density measurement instrumentation is the only practical option for some applications from a standpoint of non-invasive and low-maintenance operation. But the question of calibration and performance is difficult since there is not a practical, physical material to use as a standard. You cannot easily “feel” if the density reading is correct.
The quality of a density measurement is composed of two parts: repeatability and accuracy. However, the accuracy of any nuclear density system is only obtained after it is installed and calibrated on live process material since it is an inferred, rather than direct, measurement technology.