US · guidance
CMS SOM App. H, Tag V255
ANSI/AAMI RD52:2004 Requirements as Adopted by Reference 42 CFR 494.40(a)
Page 108 of 420
7.2 Microbial monitoring methods
7.2.1 General (repeat cultures)
Cultures should be repeated when bacterial counts exceed the allowable levels. If culture
growth exceeds permissible standards, the water system and dialysis machines should be
cultured weekly until acceptable results are obtained. Additional samples should be
collected when there is a clinical indication of a pyrogenic reaction or septicemia, and
following a specific request by the clinician or the infection control practitioner.
If repeat cultures are performed after the system has been disinfected (e.g., with
formaldehyde, hydrogen peroxide, chlorine, or peracetic acid), the system should be
flushed completely before collecting samples. Drain and flush storage tanks and the
distribution system until residual disinfectant is no longer detected before collecting
samples.
Interpretive Guidance § 494.40(a)
Responsible staff members must be able to describe what is done when bacterial counts exceed
action levels.
History
Rev.
Provenance
- Source
- cms.gov
- Retrieved
- 2026-07-22
- Edition
- som-2026-07-22
- Content hash
1bfd03c3b107e1f314d97fc41862b707895ab7029d7994c5b5e4a6b54edf2926
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