How often should carbon tanks be rebedded?

it all depends on your facility water policy, we do ours every 1-1/2 to 2 years, and also depends on water quality.

We do not re-bed our carbons just exchange them every 6 months to keep the bacteria level from getting to high.

We exchange 1/2 of our tanks every quarter, so each tank is in use for 6 months...unless we have high chlorine readings from one of the worker tanks. In that case, we exchange them within the next day or two.

Our facility size tanks will only be re-bed when there is break-through from the first tank, then both tanks will be re-bed as soon as humanly possible.

We run 2 small tanks on our portable equipment and they are both re-bed every 3 months.

Chuck

More and more seems like you probably need to rebed sooner rather than later because of the bacteria dilemma.

I believe CMS requires that you develope a schedule based on the last breakthrough or rebed. They want you to be pro-active. If your tanks went 5 years between rebedding then set a schedule for every 4 years. If you are an FMC clinic then you need to start rebedding annually.

I don't have the reg in front of me but I thought it said that for backwashable carbons that an iodine level needs to be taken and based on the result, which should be above 900, that is when you rebed. I'll double check this when I have the reg in front of me again.

In the CMS guidelines it is v tag 194 which references AAMI rd52:2004 5.2.5 which says GAC should have a minimum iodine number of 900. Resin sampling will get you the iodine number.