If your drinking water supply is either interrupted or contaminated and you need to prepare formula feed for a baby, it is important to be careful with the water you use. Here are some tips from the Foods Standards Agency on preparing formula safely:

• Ideally use water from a bowser (a water tank provided by water companies), or bottled water, brought to a 'rolling' boil and left covered to cool for no more than half an hour, then follow the manufacturer’s instructions on making up the feed. The use of unboiled bowser water should be avoided.
• Use cooled boiled water or cooled boiled bottled water for cooling the feed once it has been made up.
• Ready-to-feed liquid formula could be used instead.
• If there is no electricity or gas to allow boiling and you don’t have ready-to-feed liquid formula available, bottled water (table, spring or mineral water) can be used without boiling to prepare baby feeds, but the prepared feed should then be used immediately.
• Some bottled water labelled as 'natural mineral water' may have high levels of sodium or sulphate. When buying bottles of natural mineral water, look at the label and check that the figure for sodium (or 'Na') is not higher than 200mg a litre and sulphate (or ‘SO’ or ‘SO4’) is not higher than 250mg a litre. If it is, then try to use another water. If no other water is available, then use this water for as short a time as possible.

For more information, visit www.food.gov.uk/safereating/microbiology/flood.