510(k) · Cleared

Cleared

TDS Standard Solution

K191496510(k) TraditionalCleared Aug 5, 201961-day reviewClass II21 CFR 876.5820

Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly, last Nov 3, 2026

Mesa Laboratories, Inc. · FKH Solution-Test Standard-Conductivity, Dialysis

Cleared on Aug 5, 2019 as substantially equivalent to K033330 (Mesa Laboratories, Inc., 2004) after a 61-day review. Its family tree reaches back 2 generations to 1985.

Decided: Aug 5, 2019
Review: 61 days
Class: Class II
Product code: FKH
Recalls: None
Predicates: 1

Its longest line of descent runs back 2 generations to K851362 (1985). No later device cites it as a predicate yet.

By dateBy generation

Root · 2 generations backK851362 Standard Solution of Conductivity & Measurement ofRna Medical Corp. · 1985
1 generation backK033330 Conductivity/TDS Calibrator SolutionMesa Laboratories, Inc. · 2004 · Recalled
This deviceK191496 TDS Standard SolutionMesa Laboratories, Inc. · 2019

View FIG. 1 as a table

Line of descent and top descendants

Generation	Number	Device	Applicant	Decided	Recalls
−2	K851362	Standard Solution of Conductivity & Measurement of	Rna Medical Corp.	1985	—
−1	K033330	Conductivity/TDS Calibrator Solution	Mesa Laboratories, Inc.	2004	1
0 (this device)	K191496	TDS Standard Solution	Mesa Laboratories, Inc.	2019	—

FIG. 1 — Lineage of K191496, 1985–2019Source: FDA 510(k) summaries, read by 510(k) Report · How lineage is built

Sources: FDA 510(k) database (decision fields), the FDA summary (predicates and indications), FDA recall and enforcement reports, and MAUDE; processed by 510(k) Report. Verify on FDA.gov · Methodology and accuracy.

Planning a device in FKH? A 510(k) Report weighs predicate choices, recall history and review times for a new device like this one.

Candidate predicates for a device like this, rankedin the report
Recall history across each candidate’s familyin the report

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What was it cleared against? (1)

Devices the submitter claimed this one is substantially equivalent to (*), and reference devices cited for a specific test or feature (†), as written in the FDA summary.

Type	Number	Device	Applicant	Decided	Recalls
*	K033330	Conductivity/TDS Calibrator Solution Summary page 4 …sis Product Code 78 FKH Predicate Conductivity/TDS Calibrator Solution Device(s): Mesa Laboratories Inc 510(k) Number K033330 Cleared February 4, 2004 Device The device consists of salts (Sodium Chloride, Sodium Description:…	Mesa Laboratories, Inc.	2004	1
†	K955298	Phoenix Dialysate Meter	Automata Medical Instrumentation, Inc.	1996	—

Also cleared against K033330: 1 other device →

What descends from it?

No later submission names this one as a predicate yet.

Has anything in its family been recalled? (0 Class I)

No FDA recall names this device.

No ancestor or descendant has a Class I recall.

What does this lineage say?

The line of descent spans 34 years and passes through 2 companies; a new generation was cleared every 18.7 years on median.
1 of the 2 ancestors has a recall of any class.
1 other device also cites its predicate K033330.

How does its category compare?

All FKH devices

FKH Solution-Test Standard-Conductivity, Dialysis: FDA decisions, review times, recalls and adverse event reports over 20 years. 2019, this device’s year, is highlighted.

FDA decisions per year · FKH

1in 2019

2007high 1 (2013) · low 0 (2007)2026

2026 to Oct 25, outlined.

Median 510(k) review, days · FKH

Too few FKH 510(k)s in any year since 2007 to give a median.

Recalls per year · FKH

No recall names FKH since 2007.

Adverse event reports per year · FKH

2in 2013

2007high 2 (2013) · low 0 (2007)2025

MAUDE reports naming product code FKH, not matched to any one device; reports are not rates.

View these four charts as a table

Year	Decisions	Median 510(k) review, days	MAUDE reports
2007	0	—	0
2008	0	—	0
2009	0	—	0
2010	0	—	0
2011	0	—	0
2012	0	—	0
2013	1	—	2
2014	0	—	0
2015	0	—	0
2016	0	—	0
2017	0	—	0
2018	0	—	0
2019	1	—	0
2020	0	—	0
2021	0	—	0
2022	0	—	0
2023	0	—	0
2024	0	—	0
2025	0	—	0
2026	0	—	—

What is it indicated for?

This TDS Standard Solution is indicated for verifying the accuracy (calibration) of TDS (Total Dissolved Solids) meters. This standard solution should be used immediately before conductivity meters are used to determine the conductivity of water obtained from water purification systems used in hemodialysis. This solution is prepared from a mixture of salts comprised of 40% Sodium Bicarbonate, 40% Sodium Sulfate, and 20% Sodium Chloride which is intended to mimic natural water systems. These solutions are used remotely from the water purification equipment, and do not come into contact with the patient.

Indications for use as stated in the FDA summary.

https://510kreport.com/device/K191496 · printed Nov 6, 2026

Cite this page

510(k) Report. “K191496: TDS Standard Solution.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 6, 2026. https://510kreport.com/device/K191496

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Record history

FDA decision record loaded May 2, 2026
Summary read Oct 13, 2026 (extraction version 9eaa42aa01ed)
Lineage and recalls computed Nov 3, 2026
Page last updated Nov 3, 2026