An oxygen concentrator is a medical device that filters ambient air to provide supplemental oxygen. It draws in room air (about 21% oxygen) and uses Pressure Swing Adsorption to separate nitrogen and other gases, delivering a concentrated stream of oxygen. The therapeutic benefit depends entirely on the purity of the oxygen it delivers, making regular verification of its performance essential for safety. If the concentration falls below the prescribed level, the user may not receive the necessary therapeutic dose, potentially leading to serious health complications. Understanding how to check the device’s function is important for anyone relying on this technology.
Basic Operational Checks
A user or caregiver can perform simple, non-technical checks daily to ensure the machine is operating correctly. These visual and audible confirmations establish the baseline for the concentrator’s physical integrity and immediate functionality.
Start by confirming the device is receiving power, looking for a steady green light or status indicator on the control panel. Many modern concentrators feature internal monitoring systems that display yellow or red warning lights to signal problems with purity or pressure. Check the flow meter to ensure the ball is centered on the flow rate prescribed by the physician, confirming the setting has not been accidentally altered.
Visual inspection of the oxygen delivery system is necessary to prevent restricted flow. The nasal cannula or mask tubing must be free of kinks, blockages, or excessive condensation that could impede gas flow. Concentrators rely on proper airflow, so confirm that air intake filters are clean. The machine must be placed at least 6 to 12 inches away from walls, furniture, or curtains to ensure proper ventilation.
Listen for any unusual operational noises, such as grinding, sputtering, or a change in the typical rhythmic sound of the compressor cycling. Excessive heat radiating from the machine can also be a sign of an internal mechanical issue or blocked ventilation. These simple, non-invasive checks often catch common causes of reduced efficiency, like a dirty filter or a kinked tube.
Measuring Oxygen Purity and Flow Rate
The only definitive way to measure the actual oxygen concentration is by using a specialized tool called an oxygen analyzer, or purity meter. This equipment provides a precise, objective measurement of the oxygen percentage in the gas stream exiting the machine. Since the average user does not typically own this equipment, the test is generally performed by a medical equipment supplier or a trained technician during routine maintenance.
To perform the test, the concentrator must run for at least 15 to 20 minutes to achieve stable operating temperature and purity. This time allows the internal sieve beds to fully saturate. The oxygen analyzer is then securely connected to the concentrator’s output port, often using a specialized adapter or flow diverter. The analyzer must be used at the specific flow rate setting the user is prescribed, as purity can drop as the flow rate increases.
High-quality analyzers use either an electrochemical sensor, which measures oxygen concentration via a chemical reaction, or an ultrasonic sensor, which measures the speed of sound through the gas to determine the concentration. The technician records the stabilized percentage reading from the analyzer to determine the device’s true performance. The flow rate itself should also be verified using a calibrated flow meter. This ensures the concentrator’s dial setting accurately reflects the volume of gas being delivered in liters per minute (LPM).
Understanding Test Results and When to Seek Professional Help
Interpreting purity test results is crucial for ensuring the safety and effectiveness of oxygen therapy. Medical-grade oxygen concentrators are designed to deliver a purity range typically between 87% and 95% oxygen concentration at all flow settings. If the internal purity alarm activates or a test yields a result below this accepted range, it indicates a significant problem with the filtration system.
If basic operational checks reveal a simple issue, such as a dirty particle filter, the user should follow the manufacturer’s instructions for cleaning or replacement. A kink in the tubing or a low water level in the humidifier should also be corrected immediately, as these can affect flow and pressure. These simple interventions often restore the machine’s efficiency and prevent the need for a professional service call.
If a technical purity test reveals a concentration below the medical standard, particularly under 87%, the machine must be taken out of service immediately. The World Health Organization specifies a minimum purity level of over 82% for therapeutic use; anything below this threshold is considered ineffective and potentially dangerous. A low purity reading often suggests that the zeolite material in the internal sieve beds is degraded or contaminated. In such cases, the user must contact their medical equipment provider or technician immediately for repair, sieve bed replacement, or a complete exchange of the concentrator unit.