(189 days)
The DMOS is intended to convert liquid oxygen to gaseous oxygen for delivery to a patient and/or for delivery to rescue personnel to supplement environmental oxygen at high altitudes while being carried by a rescue personnel at one-half (0.5) to fifteen (15) liters per minute (LPM) and fifty (50) pounds per square inch gauge (psig).
The DMOS, when filled with liquid oxygen, will be used to provide medical oxygen treatment to injured personnel or provide supplemental oxygen to operator during dismounted operations above 10,000 feet MSL. The DMOS provides for storing of 1.4 liters of liquid oxygen and converting this liquid into its gaseous state. The gaseous oxygen is capable of being delivered in controlled amounts to provide medical treatment to injured patients and uncontrolled amounts to drive respiratory medical devices or supplemental oxygen in high altitude. The DMOS is capable of being filled with liquid oxygen from the Oxygen Generator System (OGS) and with current liquid oxygen storage/ filling stations. The DMOS contains a thermally insulated container of liquid oxygen (LOX) that is intended to supplement gases to be inhaled by a patient. The DMOS supports medical devices provided by the user including masks, cannulas, and Bag Valve Mask (BVM) being attached to the flow control patient outlets. The DMOS is portable and can be carried onboard, tied down, transported and operationally perform on various aircraft and ground vehicles. The DMOS converts liquid oxygen from its insulated container through its heat exchanger into gaseous oxygen and finally the gaseous oxygen is available for distribution from an outlet port on the user interface.
The furnished information describes the Dismounted Medical & Supplemental Oxygen System (DMOS), a portable liquid oxygen unit. It is being compared to a predicate device, the Backpack Medical Oxygen System (BMOS) (K071581).
Here's an analysis based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state "acceptance criteria" as a separate set of pass/fail metrics. Instead, it provides a comprehensive list of "Physical and performance characteristics" that the DMOS is designed to meet, and implicitly, these act as the acceptance criteria for the device's functionality and safety. The reported device performance is indicated by the fact that the device was deemed "substantially equivalent" to its predicate after "extensive DMOS capability, performance, and environmental testing." The table below merges the stated requirements with the implied "met" status based on the submission's conclusion.
| Performance Characteristic (Acceptance Criteria) | Reported Device Performance (Implied) |
|---|---|
| Supply 93% oxygen concentration when filled from OGS | Met |
| Capable of delivering gaseous oxygen to one patient at a maximum flow rate of 15 ambient LPM | Met |
| Capable of connecting to medical mask or cannula to supply oxygen during operations above 10,000 feet MSL | Met |
| Capable of delivering oxygen to one patient at a flow rate of 5 LPM for a minimum duration of 4 hours | Met |
| Operating pressure shall be 50 ± 5 psig | Met (explicitly 50 PSIG outlet pressure) |
| LOX capacity shall be 1.4 liters | Met |
| Operate up to 35,000 feet MSL | Met |
| Overall weight, including LOX, less than 16 lbs | Met (15.3 lbs when filled with LOX) |
| Oxygen delivery pressure monitored and displayed | Met |
| Liquid oxygen quantity monitored and displayed | Met |
| Any power required by the DMOS self-contained | Met (Battery operated) |
| Capability to be filled with LOX by standard DoD and NATO servicing connectors | Met (Standard Military CRU-50/A connection) |
| Refilled in 10 minutes or less from the OGS | Met |
| Delivery Rate (outlet flow) 15 LPM @ 50 PSIG | Met |
| Delivery Temperature within +10/-20 °F of low ambient (-40 °F) and within +10/-65 °F of high ambient (130 °F) at outlet ports | Met |
| No Delivery Temperature Alarm | Met |
| 1-Person-unit has one handle | Met |
| LOX Quantity Indicator: Battery powered | Met (One 9V battery) |
| No Low Quantity Alarm | Met |
| 50 PSIG outlet pressure | Met |
| No Outlet Pressure Alarm | Met |
| Outlet Ports: 2 (DISS 1240 & Female Dixon Quick-Disconnect) | Met |
| Flow Control Valve (0.5-15 LPM, with 12 settings) | Met |
| Single-person carry | Met |
| Standards Met: DOT-4L (Production Units) | Met |
| Sterility / Shelf Life: N/A | Met |
| Electrical Safety: Tested IAW MIL-STD-810G | Met |
| Medical Devices Compatibility: Commercial Mask, Commercial Cannula, Flow Control Valve | Met |
| Fill Connection: Standard Military CRU-50/A connection | Met |
| Operating Temperature: -40°F to 130°F | Met |
| Storage Temperature: -40°F to 130°F | Met |
2. Sample Size Used for the Test Set and Data Provenance
The document does not specify a "sample size" in terms of a number of devices tested in a statistically powered study, nor does it refer to a "test set" in the context of a dataset for algorithm validation. Instead, it states that "Essex Industries, Inc. Engineering personnel completed extensive DMOS capability, performance, and environmental testing." This implies testing of physical device prototypes.
The provenance of this testing data is prospective, as it refers to testing performed on the DMOS device itself. There is no explicit mention of the country of origin of the data, but given the company's address in St. Louis, Missouri, USA, and the reference to DoD and NATO standards, it is highly likely that testing was conducted in the United States.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not applicable as the device is a physical medical device (portable liquid oxygen unit), not an algorithm that requires expert annotation for ground truth. The "ground truth" for this device's performance is established through physical and environmental benchmark testing against defined engineering specifications and regulatory standards.
4. Adjudication Method for the Test Set
This is not applicable for the same reason as point 3. Testing involves objective measurements against engineering specifications rather than interpretative decisions requiring adjudication.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
This is not applicable. The device is a physical medical device, not an AI algorithm intended for diagnostic or assistive interpretation by human readers. Therefore, an MRMC study to measure improvement with AI assistance is irrelevant.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
This is not applicable. The device is a physical medical device, not an algorithm.
7. Type of Ground Truth Used
The ground truth used for evaluating the DMOS is based on engineering specifications, direct physical measurements, and compliance with military standards (e.g., MIL-STD-810G, DOT-4L). For example:
- Oxygen concentration: Measured directly.
- Flow rates and pressures: Measured directly.
- Duration: Measured directly.
- Weight and capacity: Measured directly.
- Environmental tolerances (temperature, altitude, vibration, shock): Demonstrated through specific tests described in MIL-STD-810G.
8. Sample Size for the Training Set
This is not applicable. The device is a physical medical device, not an AI algorithm that requires a training set.
9. How the Ground Truth for the Training Set was Established
This is not applicable for the same reason as point 8.
§ 868.5655 Portable liquid oxygen unit.
(a)
Identification. A portable liquid oxygen unit is a portable, thermally insulated container of liquid oxygen that is intended to supplement gases to be inhaled by a patient, is sometimes accompanied by tubing and an oxygen mask. An empty portable liquid oxygen unit is a device, while the oxygen contained therein is a drug.(b)
Classification. Class II (performance standards).