The Westmed, Inc. BlockAide™ Filter is designed as a disposable and single-use, bi-directional filter for use in reducing possible bacterial and/or viral cross contamination of spirometers and pulmonary function testing instruments, associated valves and hoses, from aerosols and particulates, which may be present in a patient's exhaled gas. The device is indicated for diagnostic applications.

Device Description

The BlockAide™ Filter, manufactured by Westmed, Inc., is a disposable, single-use barrier type, bi-directional filter fabricated from a plastic resin that is supplied to the customer packaged and non-sterile. Fabricated with a filtering medium that is highly effective in reducing the numbers of both bacterial and viral contaminates that may be present in a patient's exhaled gas, the device's design also minimizes the resistance to air flow. The product is intended to protect both the patient and pulmonary function instruments from potential transmission of pathogens by droplets and aerosols.

The device consists of two molded plastic housings enclosing a disk of filter media. To avoid confusion, the patient housing side is made from an opaque plastic and the machine housings are fabricated from the same plastic but with different number molded into the housing to identify machine end. The numbered end fits the machine and the opaque end is for the patient side; therefore making clear definition as to which end is used for the patient and the machine.

AI/ML Overview

The provided text describes the Westmed, Inc. BlockAide™ Filter, a disposable bacterial/viral filter, and its non-clinical testing to demonstrate substantial equivalence to predicate devices. The information focuses on design characteristics and performance metrics rather than a typical clinical study with human subjects.

Here's an analysis of the acceptance criteria and the study that proves the device meets them, based on the provided text:

1. A table of acceptance criteria and the reported device performance

Acceptance Criteria (from ATS 1994 update recommendations*)	Reported Device Performance (BlockAide™ Filter)
Airflow resistance less than 1.5 cm H₂O/L/s	Average of 0.419 cm H₂O/L/sec (5.028 cm H₂O/SLPM at 720 L)
Bacterial Filtration Efficiency (BFE)	> 99.9%
Viral Filtration Efficiency (VFE)	> 99.9%
Biocompatibility (Cytotoxicity, Sensitization, Intracutaneous Reactivity)	Demonstrated to be biocompatible
Dead space	Approximately 54 mL

Note: The document explicitly mentions that the BlockAide™ Filter "met the recommendations of the American Thoracic Society's Standardization of Spirometry (1994 update) for minimal recommendations for Diagnostic Spirometry Equipment with in-line filters; i.e., that the measuring equipment as attached to the filter have air flow resistance of less than 1.5cm H2O/L/s." The BFE and VFE criteria are generally accepted performance standards for such filters, even if a specific numerical "acceptance criteria" isn't explicitly stated in the document beyond the achieved performance.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

The document primarily describes non-clinical bench testing rather than studies involving human subjects or clinical data. Therefore, the concept of a "test set" in the traditional clinical sense is not directly applicable.

Sample size for testing: Not explicitly stated for each test (BFE, VFE, Airflow resistance, Biocompatibility). The tests likely involved a sufficient number of devices/samples to ensure statistical validity for the respective tests, but the exact count is not provided.
Data Provenance: The tests would have been conducted in a laboratory setting, likely in the United States, given Westmed, Inc. is based in Tucson, AZ, USA, and the submission is to the FDA. The data is prospective in the sense that the tests were performed specifically for the 510(k) submission.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

Not applicable. For non-clinical bench testing of a medical device like a filter, "ground truth" is established by adherence to recognized testing standards and validated methodologies (e.g., ISO, ASTM standards for filtration and biocompatibility, or established protocols for airflow resistance). The expertise lies in the laboratory personnel conducting these tests and their adherence to these standards. There is no mention of external experts establishing a "ground truth" for the test results themselves.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

Not applicable. Adjudication methods like 2+1 or 3+1 are typically used in clinical studies for interpreting ambiguous clinical data or images. This document describes objective, quantitative non-clinical tests with measurable outcomes.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

Not applicable. This device is a physical filter, not an AI-powered diagnostic tool. Therefore, an MRMC study or AI assistance is not relevant to its evaluation.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

Not applicable. This device is a physical filter, not an algorithm.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

The "ground truth" for the performance claims is derived from objective, quantifiable laboratory measurements obtained through standardized testing protocols:

Bacterial/Viral Filtration Efficiency: Established by challenging the filter with known concentrations of bacterial or viral aerosols and measuring the reduction in concentration downstream. The "ground truth" is the measured efficiency against the challenge organism/particle.
Airflow Resistance: Measured directly using calibrated flow and pressure sensors. The "ground truth" is the physical property of resistance to flow.
Biocompatibility: Determined by standardized in-vitro and/or in-vivo tests as per ISO 10993-1 guidelines (cytotoxicity, sensitization, intracutaneous reactivity). The "ground truth" is the biological response observed under controlled conditions.

8. The sample size for the training set

Not applicable. The BlockAide™ Filter is a physical medical device, not a machine learning or AI model, so there is no "training set."

9. How the ground truth for the training set was established

Not applicable, as there is no training set for this type of device.

Summary

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4.0 510(k) Summary

In accordance with 21 CFR sections 807.92, Westmed, Inc. is submitting the following 510(k) summary:

K1773

DEC

ﮯ ۔

Date of Preparation 4.1

May 18, 2012

Submitter Information: 4.2

Westmed, Inc. Company Representative: R. Jon McKinnon, President 5580 S. Nogales Highway Tucson, AZ 85706 United States USA FDA Registration No .: 2028807 Owner / Operator No .: 9006543

Preparer of Submission and Contact for Information: 4.2

Westmed, Inc 5580 S. Nogales Highway Tucson, AZ 85706 United States Telephone: (800) 724-2328 / Fax: (520) 294-2780

R. Jon McKinnon (contact for correspondence and information) Telephone: (800) 724-2328 / Fax (520) 294-2780

4.3 Name of Device:

Proprietary Name:	BlockAide™ Filter.
Common Name:	Disposable bacterial/viral filter.
Classification Name:	Breathing circuit bacterial filter, [21 CFR 868.5260(a)].
Regulation Number:	21 CFR 868.5260(a) for Breathing circuit bacterialfilters.
Product Code:	73 CAH
Class:	Class II (performance standards)

Page 9 of 115

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Substantial Equivalence: 4.4

This submission establishes the substantial equivalence of the Westmed, Inc. BlockAide™ Filter to five predicate devices:

The All Flow Pulmonary Filter, (1)
K043148, SE letter: 12/13/04.
The SpiroSafe Disposable PF Filter, (2) (3)
K973314, SE letter: 11/21/97. K934475, SE letter: 10/21/93.
The KOKO Disposable PF Filter II, The MicroGard Disposable PF Filter,
- K934272, SE letter: 11/24/93.
The MultiSPIRO Disposable PF Filter, K951410, SE letter: 04/24/95. (5)

Description of the Device: 4.5

(4)

Figure I Example of Filter Part No. 6901-E with patient and machine housing components separated:

Image /page/1/Picture/14 description: The image shows three circular objects on a dark background. Two of the objects appear to be the lids of containers, with intricate designs and a hole in the center. The third object is a solid, round disc with a textured surface, and an arrow points towards it.

Opaque machine housing with number

Filter medium Page 10 of 115 Opaque patient housing with mp

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Figure 2, Example of filter assembled:

Image /page/2/Picture/2 description: The image shows a dark, grainy photo of a vase. The vase is dark in color and has a rounded body with a cylindrical neck. The background is black, which makes it difficult to see the details of the vase. The image is low quality and has a lot of noise.

Because spirometers can have different sensor diameters, the BlockAide™ Filter is available in six different sizes with a number that correlates with their respective part numbers. The following chart lists the size and number of each model:

Filter Chart

BlockAide™ FilterPart No.	number combination(patient housing / machinehousing)	I.D / O.D (mm)
6901-R/E	Opaque / Opaque 1	27.23 / 30.18
6902-R/E	Opaque / Opaque 2	34.48 / 33.15
6903-R/E	Opaque / Opaque 3	45.47 / 47.45
6904-R/E	Opaque / Opaque 4	26.26 / 28.73
6905-R/E	Opaque / Opaque 5	29.52 / 32.77
6906-R/E	Opaque / Opaque 6	37.39 / 33.63

Intended Use of the Device: 4.6

The BlockAide™ Filter is designed as a disposable and single-use bi-directional filter for use in reducing possible bacterial and/or viral cross contamination of spirometers and pulmonary function testing instruments, associated valves and hoses, from aerosols and particulates, which may be present in a patient's exhaled gas. The device is indicated for diagnostic purposes.

Technological Characteristics in Comparison to the Predicates: 4.7

The BlockAide™ Filter has no differences in Technological characteristics and is substantially equivalent to the five predicate devices with respect to the following design characteristics and functions:

The devices are intended for use in reducing the possible cross contamination 1. of spirometers and pulmonary function testing instruments from bacterial and/or viral pathogens by droplets, particulates, and/or aerosols.

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The devices function as a barrier type, bi-directional filter, which is within a 2. sealed double port assembly, with one port contacting the patient's mouth and the other port to be attached to the spirometers or pulmonary function-testing instrument.
The device housing components are fabricated from the same or similar 3. The 'donoo noderials used in the predicate devices. The filter media is the same as or similar to that used in the predicate devices. These materials have long and extensive use in medical device applications.
The devices have been demonstrated to function effectively in reducing high 4. challenge numbers of bacterial and viral contaminates.
The devices provide air filtration while minimizing alrflow resistance through ട്. the filter assemblies to the pulmonary test equipment.
The BlockAide™ Filter met the recommendations of the American Thoracic 6. Society's Standardization of Spirometry (1994 update) for minimal Society S - Otandardization - of Spirometry Equipment with in-line filters; i.e., that the measuring equipment as attached to the filter have air flow resistance of less than 1.5 cm H₂O/L/s.

Conclusions drawn from the Non-Clinical Tests: 4.8

Data provided in this submission indicate that the basic functional characteristics of the BlockAide™ Filter are substantially equivalent to those of the predicate devices.

Bacterial Filtration Efficiency (BFE) testing demonstrated the BlockAide™ Filter, at an increased chailenge, to be %BFE = > 99.9%.
Viral Filtration Efficiency (VFE) testing demonstrated the BlockAide™ filter, at an increased challenge, to be %VFE = > 99.9%.
Airflow resistance testing demonstrated the device to an average of 5.028 cm ' 2. H2O/SLPM at 720 L. (Ref. 760 mm HGA 70 °F), which is approximately 0.419 cm H2O/L/sec.
Filter dead space was demonstrated to be approximately 54 mL. 3.
The BlockAide™ Filter meets the recommendations of the American Thoracic 4. Society's Standardization of Spirtometry (1994 update) for minimal recommendations for Diagnostic Spirometry Equipment with in-line filters i.e., that the measuring equipment as attached to the filter have air flow resistance of less than 1.5cm H2O/L/s.
The device was categorized as a surface device with skin and mucosal 5. membrane and as an external communicating device with tissue contact both for limited <24 hours contact. As such per FDA Memorandum G-95 Table 1 the following tests were conducted per ISO 10993-1 cytotoxicity, sensitization and intracutaneous reactivity. This testing showed the device to be biocompatible.

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DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/4/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES • USA" around the perimeter. Inside the circle is a stylized symbol that resembles three overlapping human figures.

Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-002

Public Health Service

December 6, 2012

Mr. R. Jon McKinnon President Westmed, Incorporated 5580 South Nogales Highway TUCSON AZ 85706

Re: K121382

Trade/Device Name: BlockAide™ Filter Regulation Number: 21 CFR 868.5260 Regulation Name: Breathing Circuit Bacterial Filter Regulatory Class: II Product Code: CAH Dated: November 14, 2012 Received: November 23, 2012

Dear Mr. McKinnon:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

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Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please go to http://www.fda.gov/AboutFDA/CentersOffices/CDRH/CDRHOffices/ucm115809.htm for the Center for Devices and Radiological Health's (CDRH's) Office of Compliance. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm.

Sincerely yours,

Kwame Q. Ulmer

Anthony D. Watson, B.S., M.S., M.B.A. Director

Division of Anesthesiology, General Hospital, Respiratory, Infection Control and Dental Devices

Office of Device Evaluation Center for Devices and

Radiological Health

Enclosure

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INDICATIONS FOR USE STATEMENT

510(k) Number (if known): K121382

BlockAide™ Filter Device Name:

Indications for Use:

The Westmed, Inc. BlockAide™ Filter is designed as a disposable and single-use, bi-directional The Wolthou, in reducing possible bacterial and/or viral cross contamination of spirometers and hiter for ass in roducing poculars, associated valves and hoses, from aerosols and particulates, which may be present in a patient's exhaled gas. The device is indicated for diagnostic applications.

2 OR Prescription Use (part 21 CFR 801. Subpart D)

Over-the-Counter Use (part 21 CFR 801 Subpart C)

(PLEASE NO NOT WRITE BELOW THIS LINE -- CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CRDH, Office of Device Evaluation (ODE)

Lester W. Schultheis Jr 2012.12.07 1/2:36:36 -05'00'

(Division Sign-Off) (Division Sign-Off)
Division of Anesthesiology, General Hospital
Division of Anesthesiology, General Devices Division of Arcol. Dental Devices

K121382 . 510(k) Number:

000010 Rev A

Regulation Number and Section

§ 868.5260 Breathing circuit bacterial filter.

(a)
Identification. A breathing circuit bacterial filter is a device that is intended to remove microbiological and particulate matter from the gases in the breathing circuit.(b)
Classification. Class II (performance standards).