Point of Use Filters
To protect against any bacterial contamination that a risk analysis would deem problematic, either bioburden reduction or sterilizing filters would be implemented at point of use outlets off the water distribution loop.
Filters are implemented throughout PW processes to optimize system performance, prevent unwanted contamination and extend the life of expensive RO/DI and Distillation components. CPF's PPD Filters are constructed with high purity pleated polypropylene depth media for prefiltering critical water. These filters have superior retention and protect downstream filters by removing large amounts of particulate.
GDMB and NSPD filters are part of Critical Process Filtration's economical, general service product line. These filters are used to remove particles from raw water or from treatment steps such as softeners, mixed media bed or carbon filters. They also remove particles that could prematurely foul the RO system.
Bioburden Control and Sterilizing
Filters can be installed anywhere there is a possibility of bacterial contamination. Your process risk assessment would determine the type and placement of filters. Although a properly functioning RO system should be capable of producing bacteria free water, the potential for low level microbial contamination downstream still exists. Reducing bioburden is accomplished with a BPS filter (Polyethersulfone (PES) membrane) or BNM filter (Nylon 6,6).
More often though, water system operators install a CPF SPS, PPS, DPPS, or HPPS 0.22 or 0.10 micron validated PES sterilizing filter after the RO system as an added step of insurance and to optimize water quality. Choosing the correct PES filter will be determined by load burden, flow rate, life expectancy and system cleaning requirements. For operations requiring nylon media, the PNM sterilizing filter is the best choice.
CPF's PTR filters can prevent environmental and process gas sources of bacteria and contaminants. These hydrophobic sterilizing filters are made with Polytetrafluoroethylene (PTFE) membrane to capture microbials as air/gas enters a tank.
When keeping endotoxins out of your process is required, they can be eliminated with either of our positively charged endotoxin removal filters. For both sterilization and removing endotoxin, PPC Filters, made with a double layer of PES, are validated for absolute bacteria retention and also capture negatively charged debris. Depending on level of contaminant and flow rate, PPC filters will typically exhibit > 3-log removal of endotoxin.
If you are already using a sterilizing filter, our general purpose GPC Filter, made from a single layer of PES, can be added to capture negatively charged biological contaminants.