I am almost positive that you can't boil the Altera metal head. I always pack my baby bottle sterilizer. It is a pain in the butt, but I don't really know what else to do, other than buying a sterilizer when I get to my destination.
Edited to add: I just read this on Cayston's website:
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<span>The Altera Nebulizer Handset may also be disinfected by boiling the parts, including the Aerosol Head, in a clean pot of distilled water for a full 5 minutes. <span>Do not boil in regular tap water, as it may damage the Aerosol Head.
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