How to Check the Oxygen Purity of Your Oxygen Concentrator

At first, everything seems normal. The oxygen concentrator is running, the nasal cannula is in place, and the air feels steady. But deep down, something doesn’t feel right. You’re still tired, short of breath, or lightheaded. You start to wonder how to check the oxygen purity of your oxygen concentrator.

Oxygen purity isn’t something you can see or feel. When it drops, your body often notices first. You may feel weak, confused, or unusually breathless. Some machines also flash warning lights or beep when purity levels fall below safe limits.

This guide explains how to test your oxygen level using a purity analyzer or pulse oximeter. You’ll learn what the numbers mean, what signs to watch for, and when it’s time to get your device checked. That way, you can breathe easier with confidence.

Why Oxygen Purity Is Critical for Your Daily Health

Oxygen purity plays a major role in how well you breathe, think, move, and recover each day. The ideal purity range is between 87% and 96%, which supports strong lungs and dependable therapy results.

When your device delivers air below this range, the effects may not be seen right away. But your body will notice. You may feel more tired, out of breath, or mentally foggy during normal daily tasks.

People with COPD or lung damage are especially sensitive to small dips in oxygen quality. These dips can lead to poor sleep, slow recovery, chest tightness, or a constant need to rest.

If oxygen purity stays low, your body begins to work harder for each breath. Over time, this added stress affects heart rate, movement, energy levels, and even how well you digest food.

You may also feel lightheaded, notice pale skin, or have trouble staying awake through the day. These are all signs the oxygen purity is outside the safe zone and not supporting proper oxygen saturation.

Machines don’t always warn you. Sometimes they beep, but other times the drop goes unnoticed unless you check. That’s why it helps to use a pulse oximeter and check your oxygen therapy health effects regularly.

When you maintain proper oxygen purity, your lungs stay protected, your mind stays alert, and your comfort improves. Regular purity tests keep your therapy effective and make each breath feel steady and comfortable throughout the day.

How Oxygen Concentrators Create Medical-Grade Oxygen

Your oxygen concentrator doesn’t use oxygen tanks. Instead, it creates medical-grade oxygen from the air around you. This air has about 21% oxygen, but the machine separates and purifies it before sending it to your lungs. 

Let’s break down how this clean oxygen delivery process works.

• Air Intake: The machine begins by pulling in room air through a small intake vent. That air includes oxygen, nitrogen, and moisture. This is the same air you breathe in every day.
• Compressor: Next, the air moves through a compact compressor. This step increases the air pressure evenly and safely. The pressure helps force the air through the next filter stage.
• Sieve Bed with Molecular Filter: Pressurized air passes through the sieve bed, which contains a molecular sieve. This filter captures nitrogen from the mix. Oxygen is left behind, now in a much purer form than regular air.
• Nitrogen Exit Valve: The nitrogen that gets trapped exits the machine through a one-way valve. This keeps only the clean oxygen inside. No part of the nitrogen stays in the final airflow.
• Oxygen Outlet Tube: Finally, purified oxygen travels through a thin tube and reaches your nasal cannula. This oxygen supports steady breathing and better oxygen saturation levels for therapy success.

How to Check the Oxygen Purity of Your Oxygen Concentrator

Sometimes your oxygen concentrator sounds normal, yet you still feel breathless or tired during the day. That doubt makes you wonder if the machine is giving the right oxygen purity that your body depends on. 

The good news is, you can easily find out by testing the output with a small device called an oxygen analyzer. It gives you clear readings that confirm your concentrator’s performance and purity accuracy.

Follow these exact steps to run a proper test and understand what the results really mean.

Step 1 – Turn On Your Oxygen Concentrator

Begin by powering on your concentrator as you normally would for daily use. Make sure it's plugged in properly. Listen for any unusual sounds. A steady hum usually means the machine is running correctly. You’ll need to give the machine time to warm up before testing begins.

Step 2 – Let the Machine Warm Up for Five to Ten Minutes

Allow the concentrator to run for at least five full minutes before you check purity. This warm-up time helps stabilize the internal pressure and prepares the sieve bed to filter gases properly. A rushed test may show false readings, especially if the machine hasn't reached full output yet.

Step 3 – Set the Correct Flow Rate Based on Your Prescription

Use the same oxygen flow setting your doctor or respiratory therapist prescribed. Most machines use a dial or screen to adjust flow. A reading taken on the wrong flow setting may show incorrect purity results and lead to confusion. Always match the setting to your medical plan.

Step 4 – Connect the Oxygen Analyzer to the Outlet Port

Take your oxygen analyzer and connect its tubing to the oxygen outlet port on your machine. Some people prefer connecting directly through the nasal cannula tubing instead. Just make sure the connection is snug and air-tight, so the analyzer can read the correct purity level.

Step 5 – Watch the Digital Screen for the Purity Reading

Turn on the analyzer and wait several seconds for the reading to stabilize. You should see a digital number appear, showing the oxygen purity percentage. This number reflects what your machine is currently producing in real time, based on the flow setting and filter condition.

Step 6 – Compare the Result Against the Safe Purity Range

A healthy reading should fall between 90% and 96% for most home concentrators. Some small machines read slightly lower. If your number drops below 87%, the oxygen purity is too low and needs attention. Clean your filter, restart, and test again. If it stays low, call your supplier.

Step 7 – Test Weekly or Monthly Based on How Often You Use Oxygen

If you rely on oxygen daily, check the purity once a week to catch early issues. For part-time use, testing once a month is usually enough. Regular checks help avoid breathing problems and keep your therapy on track without guesswork.

Read the Indicator Lights and Alarm Sounds Carefully

Most oxygen concentrators use lights, beeps, and alerts to show problems before symptoms begin. These signals can help detect low purity or blocked airflow early. Quick action can keep your therapy steady and safe. The table below explains each signal, what it means, and what to do next.

Signal	What It Means	What You Should Do
Red Light	A serious issue has occurred. Purity is too low, or the machine stopped working properly.	Stop using the device right away. Switch to backup oxygen and call your oxygen supplier.
Yellow Light	The machine is warming up, or the flow is not reaching expected levels.	Wait five minutes. Then check tubing, cannula placement, or the flow setting.
Beeping Sound	The unit may have low purity, blocked tubing, or electrical issues.	Count the beeps. Check for loose tubing, a dirty filter, or a recent power loss.
Error Code	A built-in system alert shows a specific problem with a function or airflow.	Write down the code. Look in the manual or call support for the exact meaning.

 

These alerts can prevent bigger problems later. Respond quickly, even if the machine appears to work normally. Early action keeps oxygen therapy steady, safe, and fully effective for daily use.

Listen Closely to Your Machine’s Normal Sound

Every oxygen concentrator makes a sound while running, but not every sound means trouble. A calm, steady hum is normal and usually a sign of healthy operation. 

When the noise suddenly changes, it often means the machine needs attention before performance drops. Noticing small sound differences early can prevent bigger problems later and keep your therapy reliable.

Here is how to understand what each type of sound means and what action to take next.

Level 1 – Normal Sound (Everything Is Working Fine)

Most working concentrators produce a soft hum, like a quiet fan running in the background. That sound stays steady. You may also hear gentle airflow or a slight clicking sound when the flow changes. These are normal and show the machine is operating as it should.

Some models make a quiet fan noise that comes and goes throughout the day. This helps control internal heat. None of these sounds should be loud, sudden, or harsh. A machine that stays quiet and consistent usually means oxygen purity is within a healthy range.

Level 2 – Questionable Sound (Check the Machine Soon)

A louder hum, occasional clicking, or soft rattling could mean something is wearing down or slightly blocked. These signs may point to a loose filter, misaligned tubing, or early changes inside the compressor system.

If you hear this more than once, check the tubing connection and clean the external filter. Also, test the purity using your analyzer. If numbers stay low or noise keeps getting louder, contact your oxygen provider for support.

Level 3 – Concerning Sound (Stop Use Immediately)

Harsh rattling, grinding, or repeated loud vibrations signal a serious issue inside the machine. These sounds can come from broken parts, sieve bed damage, or failing compressor pressure.

If the sound is loud and followed by beeping or blinking lights, stop using the concentrator immediately. Switch to your backup oxygen source if available. Then call your supplier or technician for help and further inspection.

Use a Pulse Oximeter as an Alternative Check

Oxygen machines can run without showing visible signs of a problem. But sometimes the body feels something first. If you feel tired, dizzy, or short of breath, a pulse oximeter can help confirm your oxygen status. It offers a quick way to monitor your blood oxygen level at home.

This small tool clips onto your finger and measures something called SpO2, which stands for blood oxygen saturation. Always place it on a clean, dry finger, usually the index or middle finger of either hand. Your hand must be relaxed and warm for the reading to work correctly.

Wait several seconds for the screen to display your results. A normal SpO2 reading is usually between 94% and 98%. Anything lower than 90% may point to poor oxygen delivery. That number can warn you before bigger problems appear.

It’s important to know that pulse oximeters do not measure oxygen purity. They only check how much oxygen is entering your bloodstream. They do not replace an oxygen analyzer, but they’re helpful when symptoms appear suddenly.

If your SpO2 level stays low during normal use, clean your machine’s filter and recheck. If the number is still low, call your oxygen provider immediately. Acting early protects your breathing and helps avoid future complications.

Check the Flow Meter and Filter for Blockages

Even when your machine is on, the oxygen may not flow as it should. Sometimes the problem is simple. A blocked filter or flow issue can limit oxygen output without setting off alarms. Here’s how to spot these problems fast and fix them safely.

Problem: Oxygen Feels Weak or Flow Seems Off

Look for these warning signs if something feels wrong:

• The nasal cannula feels like it has less airflow than normal during regular use
  
• Tubing looks fine, but pressure feels weak or pulsing instead of steady
  
• No visible movement in the bubble humidifier (if your unit uses one)

Check: Look at the Flow Meter and Inspect the Filter

Start by checking the flow meter. Make sure the ball or indicator matches your prescribed LPM setting. Most users run between 1 and 5 LPM based on medical needs.

Next, locate the external filter. It’s usually found on the side or back of the machine. A clean filter should be light-colored and easy to breathe through. Dust, discoloration, or dampness can block airflow.

Inspect the tubing from end to end. Look for moisture buildup, kinks, or pinched spots that could block oxygen.

Fix: Clean the Filter and Reset the Flow

Remove the filter gently and rinse it with clean water, only if your model supports washable filters. Let it dry fully. Replace it if worn out or discolored.

Reset your flow meter to the correct level. Then turn the machine back on and wait a minute. If the airflow still feels weak, call your supplier for further troubleshooting.

When to Retest, Recalibrate, or Call for Help

Sometimes your oxygen machine looks fine, but the numbers still seem wrong. A few extra steps can help confirm what’s really happening. These three clear steps help you decide when to retest, recalibrate, or ask for expert support.

Step 1 – Retest When Something Changes

After moving your machine, running a deep clean, or noticing symptoms, retest the oxygen purity right away. Let the machine run for at least five minutes before checking. That gives it time to stabilize. 

Always make sure the flow setting matches your prescribed rate before starting any new reading. If the analyzer shows a low number after cleaning or adjusting, wait a moment and test again.

Step 2 – Recalibrate If the Analyzer Gives Unusual Results

An oxygen analyzer can drift out of calibration, especially if it’s older or rarely maintained. If readings jump or seem off between tests, the sensor may need recalibration using calibration gas. 

Some devices need a technician to reset the purity accuracy. Others include a calibration port for home use. When in doubt, check the analyzer manual or contact your provider before assuming the machine is at fault.

Step 3 – Call for Help If the Problem Continues

If readings stay low after testing and recalibration, stop using the machine and call for help immediately. Contact your oxygen supplier or medical provider if the number doesn’t improve after filter checks and resets. 

Low purity over several hours may mean a deeper issue inside the compressor or sieve bed. Fast action keeps your therapy effective and helps prevent sudden shortness of breath or oxygen failure.

Frequently Asked Questions(FAQs)

Many concentrator users follow the steps correctly but still have questions about performance and safety. These common questions cover what wasn’t explained earlier and help clear up everyday oxygen therapy concerns.

Can I leave my oxygen concentrator running all night?

Yes, most home oxygen concentrators are designed for overnight use. If your doctor recommends it, keep it running while you sleep. Always check tubing before bed to prevent flow interruptions from kinks or twists.

What’s the difference between SpO2 and oxygen purity?

SpO2 measures how much oxygen is in your blood, while purity shows how concentrated the oxygen is. A pulse oximeter checks SpO2. A purity analyzer measures output from the machine. Both are helpful for different reasons.

How do I know if my oxygen concentrator needs servicing?

Signs include weak airflow, loud vibration, flashing red lights, or a strange smell. If you have already cleaned the filter and tubing, but nothing changes, contact your provider or technician for a full device inspection.

What happens if oxygen purity drops below 87%?

Low purity may not give your body enough support. You may feel dizzy, breathless, or tired. Switch to backup oxygen immediately and call your supplier. Extended low purity can lead to serious breathing complications.

Can humidity affect the oxygen purity or machine performance?

Yes, humidity can cause filter clogs and damage internal parts. Always change humidifier water daily. Avoid placing the machine in damp areas like bathrooms or near windows. Dry airflow keeps performance steady and safe.

Conclusion

Every user deserves to know their oxygen concentrator is working the way it should. That includes seniors, caregivers, and anyone managing home oxygen therapy. The best way to build trust in your device is through regular checks.

Use your analyzer weekly, watch for warning lights, and listen closely for sound changes. These habits take only minutes but can help prevent major issues. Stay alert, follow your routine, and give yourself the breathing confidence every oxygen user deserves.