Parents are being urged to check the flower-shaped symbol on their hot water bottles before use, as it reveals the manufacturing date and helps determine if the bottle needs replacing. The warning follows figures from the International Burn Injury Database showing that 239 children suffered life-altering burn and scald injuries caused by hot water bottles in 2025.
Hot water bottles are a popular way to stay warm during colder months, particularly for children who may struggle to get comfortable in a cold bed. However, over time the rubber material can deteriorate, making the bottle more likely to split, leak or burst when filled with hot water. This can cause serious burns, especially if the water spills onto someone's skin.
How to read the flower symbol
The small flower-shaped symbol found on many hot water bottles is more than just a marking. It provides important information about when the bottle was manufactured. The symbol consists of a number in the centre, surrounded by 12 segments resembling the petals of a flower.
The number in the centre represents the year the hot water bottle was made, while the 12 segments around it represent the months of the year. The small dots inside the segments indicate the week of manufacture. This allows households to work out approximately when their hot water bottle was produced without needing a receipt or remembering when it was bought.
For example, a bottle displaying the year 2021, with the relevant month and week markings, was manufactured in April of that year. This would make that hot water bottle more than two years old, meaning it should no longer be used and needs to be replaced.
Safety precautions for use
People are advised not to use hot water bottles that are more than two years old and to regularly check them for signs of wear and tear. Alongside checking the age of the bottle, there are several other precautions households should take to reduce the risk of burns and scalds.
The Lullaby Trust advises parents never to leave a hot water bottle inside a baby's sleep space. Instead, it can be used to warm the bed before being removed completely before the baby is placed down to sleep. Hot water bottles should also never be placed directly against the skin, and a suitable cover should always be used to provide a protective layer.
Parents should also remind older children not to sit or lie on top of their hot water bottles, as this can put pressure on the rubber and increase the risk of damage.
