# K243898: Chlorine Sentinel II

- Pathway: 510(k) (Traditional)
- Applicant: Nelson Environmental Technologies, Inc.
- Decided: Apr 11, 2025 after 113 days
- Product code: MSY (Strip, Test, Reagent, Residuals For Dialysate, Disinfectant)
- Device class: 2
- Regulation: 21 CFR 876.5665
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 2 generations back to K090338 (2009). 2 ancestors in all.
No later device cites it as a predicate yet.
0 of 3 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K193169: Nelson Sentinel Series Basic Chlorine Sentinel, Nelson Environmental Technologies, Inc. (2020) Summary page 5.

## Indications for use
The Chlorine Sentinel Il is intended for use by hemodialysis professionals as a secondary chlorine device to provide continuous monitoring of Combined Chlorine. It is not intended to replace the primary method of monitoring chlorine as part of the hemodialysis water treatment system. It functions completely independent of the water treatment system does not come into direct contact with feed water used to prepare dialysate.

Source page: https://510kreport.com/device/K243898
Methodology: https://510kreport.com/methodology