Phonak Cassia User Manual page 9

Always use new batteries for your hearing aid.
You can return used batteries to your hearing care
professional.
Remove the battery if you are not using your hearing
aid for a long period of time.
X-ray radiation (e. g. CT scans, MRI scans) may
adversely affect the correct functioning of your
hearing aids. We recommend that you remove
them before undergoing X-ray procedures and keep
them outside the room.
Do not use your hearing aid in areas where electronic
equipment is prohibited.
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