--- title: How can I tell if my soda lime is working and still scrubbing CO2? description: How can I tell if my soda lime is working and still scrubbing CO2? --- [Skip to content](https://knowledgebase.cid-inc.com/how-can-i-tell-if-my-soda-lime-is-working-and-still-scrubbing-co2#main-content) English Show submenu for translations [![CID green](https://knowledgebase.cid-inc.com/hs-fs/hubfs/CID%20green.png?width=350&height=77&name=CID%20green.png)](https://knowledgebase.cid-inc.com/?hsLang=en) Open main navigation Close main navigation - English Show submenu for translations - [Submit a Support Ticket](https://cid-inc.com/plant-science-tools/leaf-area-measurement/ci-110-plant-canopy-imager/support/#SubmitaTicket) [Submit a Support Ticket](https://cid-inc.com/plant-science-tools/leaf-area-measurement/ci-110-plant-canopy-imager/support/#SubmitaTicket) How can we help you? - There are no suggestions because the search field is empty. 1. [CID Knowledge Base](https://knowledgebase.cid-inc.com/?hsLang=en) 2. [Photosynthesis Analysis CI-340](https://knowledgebase.cid-inc.com/photosynthesis-analysis-ci-340?hsLang=en) 3. [CI-340 Handheld Photosynthesis System](https://knowledgebase.cid-inc.com/photosynthesis-analysis-ci-340?hsLang=en#ci-340-handheld-photosynthesis-system) # How can I tell if my soda lime is working and still scrubbing CO2? Soda lime does have a PH-sensitive Ethyl Violet color change indicator, but this is weak and typically does not change color strongly even though the soda lime has lost strength. Adsorption of CO2 by soda lime requires moisture, so if the soda lime has dried out this will reduce scrubbing capabilities. You can test your soda lime by connecting it to the CI-340 intake. Start a measurement in Single Channel Absolute mode (S) so you are simply reading the CO2IN value. Blow into the tubing going into the soda lime column and watch the CO2IN reading on the CI-340 to see if it increases. There will be a lag time while the sample from your breath travels through the soda lime and tubing to the CO2 IRGA sensor. If the CO2 IN rises, the soda lime is probably exhausted and needs replacement. To refresh soda lime, try adding a small amount of water to the bottom of the soda lime/desiccant column. You should not add more than 5 cc of water at a time. Be sure to replace the cotton filter at either end of the plastic column of soda lime. Repeat the breath test to see if the soda lime improves at scrubbing CO2. If not, replace the soda lime with fresh and test again. - [Root Analysis](https://knowledgebase.cid-inc.com/root-analysis?hsLang=en#main-content) - [CI-602 Narrow Gauge Root Imager](https://knowledgebase.cid-inc.com/root-analysis?hsLang=en#ci-602-narrow-gauge-root-imager) - [CI-600 In-Situ Root Imager](https://knowledgebase.cid-inc.com/root-analysis?hsLang=en#ci-600-in-situ-root-imager) - [Canopy Analysis CI-110P](https://knowledgebase.cid-inc.com/canopy-analysis-ci-110p?hsLang=en#main-content) - [CI-110 Plant Canopy Imager](https://knowledgebase.cid-inc.com/canopy-analysis-ci-110p?hsLang=en#ci-110-plant-canopy-imager) - [Photosynthesis Analysis CI-340](https://knowledgebase.cid-inc.com/photosynthesis-analysis-ci-340?hsLang=en#main-content) - [CI-340 Handheld Photosynthesis System](https://knowledgebase.cid-inc.com/photosynthesis-analysis-ci-340?hsLang=en#ci-340-handheld-photosynthesis-system) - [Leaf Analysis CI-202/203/710s](https://knowledgebase.cid-inc.com/leaf-analysis-ci-202-203-710s?hsLang=en#main-content) - [CI-710s SpectraVue Leaf Spectrometer](https://knowledgebase.cid-inc.com/leaf-analysis-ci-202-203-710s?hsLang=en#ci-710s-spectravue-leaf-spectrometer) - [CI-203 Handheld Laser Leaf Area Meter](https://knowledgebase.cid-inc.com/leaf-analysis-ci-202-203-710s?hsLang=en#ci-203-handheld-laser-leaf-area-meter) - [CI-202 Portable Laser Leaf Area Meter](https://knowledgebase.cid-inc.com/leaf-analysis-ci-202-203-710s?hsLang=en#ci-202-portable-laser-leaf-area-meter) - [Software](https://knowledgebase.cid-inc.com/software?hsLang=en#main-content) - [Rootsnap!](https://knowledgebase.cid-inc.com/software?hsLang=en#rootsnap) [![felix logo 8-15-2019 transparent-1](https://knowledgebase.cid-inc.com/hs-fs/hubfs/felix%20logo%208-15-2019%20transparent-1.png?width=150&height=92&name=felix%20logo%208-15-2019%20transparent-1.png "felix logo 8-15-2019 transparent-1")](https://knowledgebase.cid-inc.com/?hsLang=en) 123 Waverly Pl., Boston, MA 02135 [mailto:sales@cid-inc.com](mailto:sales@cid-inc.com) Copyright © 2024, CID Bio-Science