Do not fill with bleach (oxygen-based or chlorine-based), petroleum products, removal solution, perfume, liquids containing large quantities of alcohol or other hazardous liquids.Do not use if the product is scratched or cracked before use.Check for leaks before use.Do not use the product at medium elevations or where there are large changes in air pressure on an airplane.Do not fill with boiling water.Do not leave on its side.Do not leave filled for extended periods of time.Immediately discontinue use if the product becomes deformed or damaged.