Kane SM14111 carbon dioxide true zero capsule

The Kane SM14111 carbon dioxide (CO2) true zero capsule for use with the Kane 457 flue gas analyser and atmosphere tester when operated in the ambient air testing mode.

For accurate ambient measurements the Kane 457 should always be zeroed using a "ZEROCAL" capsule. This capsule contains a chemical that absorbs CO2 and totally removes it from the gas stream.
Please note that these chemicals don't last forever and the capsule must be replaced at least annually. The colour of the chemicals change as more CO2 is absorbed.

For further details see the Kane 457 being used in the ambient air testing mode on YouTube:

Kane 457 operated in the ambient air testing mode on YouTube