Grainger was able to reach out to MSA Safety get some information on your question. Mine Safety Appliance has a letter of position on the shelf life and service life of their APR cartridges when in use and when stored. This information can be reviewed at the MSA website www.msasafety.com
. For further questions regarding service life on MSA cartridges contact MSA Customer Service at 1-800-672-2222.
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