Can Sodasorb be Used to Calibrate Your CO2 Sensor?

Recently we had a client ask if he could use SODASORB® as an alternative to compressed nitrogen for calibrating a CO2 sensor.

SODASORB® absorbent is intended for use in anesthesia circle systems and respiratory therapy equipment for the purpose of removing exhaled carbon dioxide. SODASORB® makes it possible for intended in-line gases to be rebreathed by the patient. As it absorbs carbon dioxide, a dye added during manufacture changes color so you can tell when it must be replaced.

We have had customers put SODASORB® in a condenser tube and push or pull air through it with a small pump to achieve low CO2 air for calibration. While SODASORB® is fine for this purpose, it is not perfect. From our observations, 10-20 ppm (parts-per-million) of CO2 will remain in the gas after being passed through the absorbent. Therefore, if using SODASORB® for calibration, you will have to bias your baseline. For example, you could first calibrate using nitrogen, then measure air passed through SODASORB®, and record the CO2 level difference in ppm. The difference would be then used to bias your recorded data.

Posted by CO2 Meter on March 25, 2014.
Subscribe to our News feed Subscribe

More news