How to store an HOCl mist and when it expires

Short answer

Look on the pack for one of two things:

• the words “best used before the end of” or an hourglass symbol, followed by a date (month and year, or day, month and year); or
• an open-jar symbol followed by a number of months, for example “12M”.

Which one appears depends on how long the product lasts. If a product lasts 30 months or less, the pack must show a best-before date. If it lasts longer, the pack can leave the date off and show an open-jar symbol with a number of months instead, unless that idea doesn't apply to the pack (Regulation (EC) No 1223/2009, article 19(1)(c), checked 19 October 2026).

Unopened vs opened

• Unopened: the date of minimum durability. The regulation describes it as the date until which the product, stored under appropriate conditions, will continue to fulfil its initial function. If storage conditions matter, the pack may print them next to the date, and the date assumes them.
• Opened: the period after opening. The open-jar symbol with a number of months tells you how long the product is meant to be used once opened.

To work out your own use-by date from the open-jar number, add that number of months to the month you first opened the pack. For example, “6M” on a pack opened in March means September. A suggestion: write the opening month on the pack with a marker when you open it, so you don't have to remember.

For what the symbols look like, see the label checklist.

Storage lines on the pack

Follow what your own label says. Two examples of what brands state, quoted as theirs and not as advice for every product (both checked 19 October 2026):

• Clinisoothe+ Skin Purifier (sold in the UK). The pack text on the brand’s ingredients page includes: “Store at room temperature. Use within 6 months of opening.” and “Avoid direct contact with clothing as may discolour fabric.” The brand’s FAQ says: “Store Clinisoothe+ out of direct sunlight and out of the reach of children.”
• Briotech, on its EU FAQ (“Handling & storage”): “For HOCl, that window can vary by formula and packaging, so it is best to check the product label when available.”

We have not checked a typical shelf life or period after opening for HOCl mists in general, so this page gives none. It varies by product; the label is the place to look.

Pouring into another bottle

Asked whether you can pour the product into another bottle or sprayer, Briotech says it recommends “dispensing from original packaging” (same FAQ, checked 19 October 2026). That is one brand’s statement. Check what your pack says, and if it doesn't say, ask the shop.

When the date has passed or you've lost track

The date applies to the product stored as the label says. If the date has passed, or you don't know when you opened the pack, don't use it. If you're unsure what your label means, ask the shop or a pharmacist.

Before you use it

For the symbols and the rest of the label, use the label checklist. Before a first use, patch-test as on the routine page.

Who to ask

If a label is unclear, or you have a skin or health concern, ask a pharmacist. This site can't answer it for you.