I would like input on portable DI's vs portable RO's for inpatient treatments provided at the patients bedside while in the hospital. Which is better? I have always thought the RO's were better and that is all I have used in an acute setting until my present job. We are currently using DI's.

Costly if you run a lot of patients.

Very expensive. I have heard that during surveys they prefer DI's. Is this right? I always thought that RO's were better for the patient because the water quality is better. How often do the carbon filters require changing? I have recently been told after each treatment but I have never in hte past had to change them between tetment. Does this depend on the type of portable RO's?

Using RO or DI is acceptable. As to cost, it depends on the quality of the incoming water. I have found that if the incoming water is less than ~150 uS/cm, DI can be cost effective as long as you have a good ultrafilter after the DI and a good resistivity meter on the eflfuent. The higher the inlet water conductivity, the more costly DI will be.

As to water quality, if your water is completely ionic from a very deep well, DI will produce water with fewer impurities than RO. But, you are not required to remove ALL impurities. You only need to remove impurities down to the AAMI limits. If your water comes from a surface water source or a shallow well, RO may produce better quality water. DI will not remove any of the non-ionic impurities from the water. The RO will remove ionic and non-ionic impurities.

I have never heard of a surveyor having a preference. As long as both are acceptable, they should accept them.

How often to change the carbon depends on what carbon filter you are using. It is preferred to have 2 carbon filters. And that the chlorine be negative after the first carbon before starting treatment.