Breath has lots of moisture. To see, just blow on a mirror and watch it fog up. Getting rid of the moisture on the mirror is easy: just wipe it off. Getting rid of moisture in a breath sample is more complex, but can be done with a bit of engineering and Nafion™ tubing. We have found ways to remove up to 90% of moisture from a patient’s breath sample.
Moisture: Why You Need it Gone?
Testing or analyzing a patient’s breath helps healthcare professionals make the right diagnosis and identify respiratory ailments quickly But, moisture in the breath sample creates problems. It can damage sensors, and that, in turn, can reduce test accuracy or worse, damage the sensor beyond repair. This can be frustrating and irritating to healthcare providers. Removing moisture can yield more accurate results and better outcomes for patients.
How Much Moisture Removal is Enough?
When removing moisture from breath samples, the term non-condensing is often used. This simply means that the moisture content in the breath sample is low enough to ensure condensation doesn’t occur at prevailing conditions.
Depending on the application, engineers and healthcare professionals aim for a higher bar. They might want to remove more moisture than what is required for the breath sample to be non-condensing. This ensures unintended condensation doesn’t happen. Also, recent technologies in breath testing and other applications benefit from having specific levels of relative humidity..
What Moisture Level Removal is Possible?
With Nafion™ tubing, up to 90% of moisture from a patient’s breath can be removed. For engineers and designers, this means that unintended condensation doesn’t happen—and they can attain tight moisture control specifications.
QUICK NOTE: When discussing moisture and water vapor, several terms are used. Relative humidity is the percentage of water vapor in the air when compared to the total amount of water vapor air can hold at that temperature, and can fluctuate with changes in temperature and pressure. Dew point is the temperature the air must be to reach 100 percent relative humidity and is more of an absolute term. At Perma Pure, when we say you can remove 90% of moisture content with Nafion tubing, we mean it as an absolute value.
Why is Precise Moisture Control Important?
For many sensors to analyze gasses most efficiently, relative humidity, or the percentage of water vapor in the air, must be at a certain level. For example, electrochemical sensors for gasses need a relative humidity level between 15% and 90% for optimal functioning. If not at this level, the water content in the electrolytes may be negatively affected. Optical sensors are arguably impacted the most by moisture as the amount of water vapor in the gas stream that is being analyzed determines the signal to noise ratio. Several engineers have come up with algorithms and smart ways to capture information – but moisture control can form a crucial part in their development.
Precise moisture control also minimizes the risk of accidently removing analytes (especially analytes that contain valuable information for diagnosis) breath samples. An incomplete sample can paint an inaccurate picture of a patient’s condition and delay proper care.
How Does Nafion Tubing Remove 90% of Moisture?
Removing certain amount of moisture from a gas stream can be achieved through expert engineering. Nafion™ tubing equilibrates to environmental conditions. One way to reduce moisture to a level that is lower than the surrounding environmental conditions, is to use a purge gas supply with a dew point that is lower than the sample gas. Typically, the purge gas will flow around Nafion™ tubing in the opposite direction of the sample gas. By doing this, you will be able to create an extremely low level of humidity seen by Nafion™ tubing.
By using Nafion™ tubing in this manner, you can remove moisture at more precise levels—and achieve humidity levels you need for optimal functioning of your device. This, in turn, will lead to better results and better outcomes for patients.
