The cellulose triacetate membrane is prone to rotting unless protected by chlorinated water, while the thin film composite membrane is prone to breaking down under the influence of chlorine. A thin film composite (TFC) membrane is made of synthetic material, and requires chlorine to be removed before the water enters the membrane. To protect the TFC membrane elements from chlorine damage, carbon filters are used as pre-treatment in all residential reverse osmosis systems. TFC membranes have a higher rejection rate of 95–98% and a longer life than CTA membranes.
We were looking for to replace an RO unit that was many years old and were impressed with iSpring's RO / UV / Ph / multi-filter options, with the More-Is-Better paradigm. Patience is required for the multipart installation because the directions are vague. We also had to run a GFCI receptacle for the UV. The UV does warm the water a bit but we remedied this by running an additional line to the fridge for cold water and ice. The system was flushed a half dozen time over two days. The initial glass was cloudy but that cleared to show some carbon from that particular filter. The water taste great and we highly recommend this drinking water system.
Despite its efficiency in killing microorganisms, UV radiation will not remove heavy metals and particles. Something else to consider is the high maintenance requirement for a UV purification system. Frequent cleaning and proper part replacement are necessary requirements in maintaining a properly functioning system. Read our article on UV water purification systems for home to find out more.
STAT: The number of annual deaths from ESD in the U.S. are unknown, since they are counted among all drownings. But anecdotal evidence shows that ESD is widespread. ESD prevention groups have successfully urged some states to enact safety standards, including the installation of ground-fault circuit interrupters and a central shutoff for a dock's electrical system.