Oxygen Concentrators Testing: What are O2 Concentrators and what are they used for?

Patients with chronic or acute respiratory and lung conditions may use oxygen concentrators. These devices continuously filter nitrogen out of the ambient air in order to supply an oxygen-rich gas stream to the user.

Oxygen concentrators deliver supplemental oxygen in the home and in hospitals. For many users, they are safer, more convenient, and more cost-effective than oxygen tanks or pressurized cylinders. The O2 concentrator market is growing thanks to increased eligibility for medical reimbursement and FAA approval of the devices for air travel.

Oxygen concentrators use two main oxygen delivery methods—pulse dose (PD) oxygen delivery and continuous flow (CF) oxygen delivery. Most O₂ concentrators operate using one of these delivery methods, however there are models in the market that are capable of both modes.

Why and when do Oxygen Concentrators require testing?

Oxygen concentrators have integrated flow and pressure sensors. These are essential for detecting patient inhalations and maintaining optimal pressures for oxygen generation. These sensors may require calibration and/or periodic checking to ensure reliability and proper operation. This often takes place during the design/manufacturing of the machine and during service.

Oxygen concentrator testing is part of these stages:

• Research and Development (R&D)
• Manufacturing and Quality Control
• Service and Calibration
• Verification of device performance between patients

Pulse dose, continuous flow, and combined oxygen concentrators are outlined below, along with the ideal TSI flow meter for testing each, but for more information please visit our application page.

Continuous Flow Delivery

Continuous flow oxygen concentrators deliver oxygen at a constant rate regardless of the patient’s breathing. Most at home or stationary concentrators use continuous flow delivery. For this delivery method, we recommend TSI low flow meter model 5200-2. This flow meter is ideal for testing and calibrating oxygen concentrators with continuous flows.

• Measures oxygen or mixed air/O2 gas flows with 2% of reading accuracy
• Provides bi-directional flow measurement that ranges from +/- 30 L/min
• Makes flow measurements in standard or volumetric flow conditions
• Added totalizer measurement can aggregate flow rate to provide total inhaled volume

Pulse Dose Delivery

Pulse dose oxygen concentrators deliver oxygen based on the user’s breathing/inhalation pattern. Pulse dose concentrators use an oxygen conserver and other technology to customize the oxygen delivery to the user’s breath rate. TSI low flow meter model 5210-2 is particularly well suited for pulse dose delivery. The 5210-2:

• Provides bi-directional flow measurements at +/-30 L/min
• Makes precise volume measurements of pulse doses varying in size or frequency
• Measures the flow rate or volume of oxygen or air/oxygen mixes with 2% of reading accuracy
• Delivers measurement readings in milliliters (mL), liters (L), or cubic feet (ft³)

Combined Delivery, Pulse Dose and Continuous Flow

Combining pulse dose and continuous flow oxygen delivery allows the oxygen concentrator to meet a wider range of patient needs. TSI low flow meter model 5210-2 is ideal for testing concentrators that can produce both types of delivery method. The 5210-2 flow meter:

• Provides volume measurements of pulse doses varying in size or frequency
• Measures the flow rate and volume of oxygen or air/oxygen mixes
• Delivers flow rate and volume measurements in milliliters (mL), liters (L), or cubic feet (ft³)
• Logs raw measurement data at 1 ms resolution and easily export as .csv files

Research and Development

For R&D applications of any oxygen concentrator type, measurements may require greater precision and accuracy. TSI flow meter 5230-2 is a great tool for oxygen therapy research and development (R&D) applications. The 5230-2:

• Makes precise volume and flow rate measurements with a +/- 1.7% of reading accuracy
• Measures the temperature, pressure, and humidity of the gas flows
• Compensates flow measurements to ensure accuracy in varying operating conditions
• Uses both standard and volumetric units for flow measurements, with customizable gas temperature and pressure standard conditions
• Logs all measurement data time at 1 ms resolution synchronized with easy export as .csv files

Measuring the Oxygen Concentration of the Gas

Please note TSI’s flow meters do not measure the concentration or ratio of the air/O₂ mix. If you need to detect the air/oxygen mix while making your measurements, use TSI’s Certifier Flow Analyzer Ventilator Test System 4070 with the Oxygen Sensor Kit 4073. This will allow you to detect the concentration of oxygen from 21% to 100% while simultaneously measuring the volume and rate of the gas flow.