CMS SOM App. H, Tag V192

5.2.5 Carbon adsorption

Two carbon beds shall be installed in series with a sample port following the first bed. A

sample port shall also be installed following the second bed for use in the event of free

chlorine or chloramine breaking through the first bed.

Refer to RD62:2001, 4.3.9 Carbon adsorption media: Carbon adsorption systems shall be

adapted specifically to the maximum anticipated water flow rate of the system. Two carbon

adsorption beds shall be installed in a series configuration.

Interpretive Guidance § 494.40(a)

ANSI/AAMI RD52:2004

5.2.5 Carbon adsorption

Carbon adsorption systems, often referred to as carbon filters, are the principal means of

removing both free chlorine and chloramine.

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Removal of free chlorine to a maximum level of 0.5 mg/L and chloramine to a maximum level of

<0.1 mg/L is necessary to protect hemodialysis patients from red cell hemolysis. In addition, free

chlorine may also degrade some reverse osmosis membranes, depending on the membrane

material.

AAMI Rationale for the Development and Provision of This Practice

A.5.2.5 Carbon adsorption

Although treatment of water by carbon adsorption is the method usually used to meet these

requirements for chloramines, the AAMI RDD Committee recognized that in certain situations,

carbon adsorption might not adequately remove chloramines. Inadequate removal of

chloramines may occur when the chloramines are in the form of naturally occurring N-

chloramines or when practices such as the use of high pH or the inclusion of orthophosphate or

polyphosphates are used (by the supplier’s water treatment plant) to comply with the EPA’s lead

and copper rule. In such circumstances, other strategies for chloramine removal may be needed

to supplement carbon adsorption. The AAMI RDD Committee is aware that adding sodium

metabisulfite prior to the reverse osmosis system has been successful in eliminating chloramine

in hemodialysis applications.

Other means of removing chloramines, such as redox alloy media and ultraviolet irradiation at

185 nm, are used in the pharmaceutical and electronics industries. These processes are currently

being evaluated for hemodialysis applications. The final choice of a system for chloramine

removal in hemodialysis settings will depend on local conditions and may require the inclusion

of more than one of the processes outlined above.

Additional Guidance: If a facility has employed supplemental strategies for chlorine removal,

these should be in addition to the use of at least two carbon tanks that hold the carbon beds. The

medical director and the chief technician should be able to discuss the rationale for the use of

supplemental strategies. Facility records should document the systems in place to protect

patients from exposure to chlorine and chloramine, and these systems should be monitored

according to the manufacturer’s directions.