According to the way European law works, existing local standards are still acceptable as legal until that standard is deemed illegal in the country of origin. Therefore because the UK has adopted the CE standard, a HSE bottle is legal in all member states as long as it is legal to use over here.
Please be advised that, after your next test, you should make sure that you carry your test certificate with your bottle. If you have one at hand the carry it with you. This is to back up the label on the bottle, which is only an indicator and not necessarily accepted as proof.
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