21 CFR 876.5665
Water purification system for hemodialysis
21 CFR 876.5665 is the regulation titled “Water purification system for hemodialysis” in 21 CFR Part 876, Gastroenterology-Urology Devices. Since 2021, 1 FDA warning letter has cited it.
- Letters citing it
- 1 since 2021
- Jan 1 to Oct 30, 2026
- 0 against 0 on the same dates in 2025
- Most often cited with
- 21 CFR 807.81, in 1 letter
- Closed out
- 100% of these letters have a published close-out
Letters citing it, by year issued
It is a medical device letter. 2026 runs to Oct 30, 2026. Pick a year to see its letters.
- 02021
- 02022
- 12023
- 02024
- 02025
- 02026
The regulation
Read the text of 21 CFR 876.5665 (eCFR, as of Sep 1, 2026)
(a) Identification. A water purification system for hemodialysis is a device that is intended for use with a hemodialysis system and that is intended to remove organic and inorganic substances and microbial contaminants from water used to dilute dialysate concentrate to form dialysate. This generic type of device may include a water softener, sediment filter, carbon filter, and water distillation system.
(b) Classification. Class II (special controls). The device, when it is a water purification subsystem disinfectant, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 876.9.
[48 FR 53023, Nov. 23, 1983, as amended at 84 FR 71814, Dec. 30, 2019]
Text from eCFR as of Sep 1, 2026.
Cited alongside it
Regulations that appear in the same letters as 21 CFR 876.5665.
Latest letters citing it
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