Helium filled balloons float because they are filled with helium gas which a harmless inert gas and does not affect the ozone layer.
LATEX BALLOONS
Please take care of your balloons for maximum enjoyment. Latex balloons can be easily punctured so keep them from sharp objects – not just pins and scissors, but sharp corners on furniture and car doors, and rough areas such as trees and bushes, brick and stone walls. Static can also make balloons burst. If possible don't place them near computers, TVs etc.
Temperature Changes
The effect of heat and cold is less noticeable in latex balloons than with foil balloons, but the gas is still expanding and contracting with the temperature. Cold will also make the latex brittle. High humidity will also affect the balloons. Keeping the balloons in an even temperature will prolong their life.
Float time
The larger the balloon the longer it will float as it holds more gas. The length of time a latex balloon will float will depend on several factors so we can never state categorically that it will float for a certain time. Latex is a natural product produced by rubber trees so is subject to inherent variations in the same way as you can't explain why some flowers in a bunch will last longer than others. Balloons will gradually deflate. The gas starts to escape from the balloons immediately but you shouldn't notice any difference for several hours. We use premium quality 28-30cm balloons which are at their best for about 12 hours. Coating the balloon with Hi-float will enable them to float for 4 days or more. They will still be shrinking, but will take much longer over it.
Using balloons outdoors
If you use your balloons outside, you have to accept they might not last very long. Not only is the temperature variable, but there's wind and rain to contend with. Just a few raindrops will make a balloon droop and the wind can whip the balloon against a wall or tree before you know it. If you want to tie the balloons to a fence or similar, we recommend that you tie them so that they are not floating, then the wind is not going to blow them about. All latex balloons will gradually oxidise (lose their shine and become dull). This will happen more quickly outdoors. Latex is a natural product and degrades at about the same rate as an oak leaf.
Summary
For maximum enjoyment, keep your latex balloons:
• away from sharp or rough objects,
• away from any source of heat,
• away from static,
• in an even temperature,
• indoors.
FOIL BALLOONS
Although foil balloons look much tougher than latex balloons, they're not really. They can be easily punctured so keep them away from sharp objects – not just pins and scissors, but sharp corners on furniture and car doors, and rough areas such as trees and bushes, brick and stone walls.
Static can also make balloons burst. If possible don't place them near computers, TVs etc.
Temperature changes
The helium in the balloons reacts to temperature so if you take them to a cooler place, the gas contracts making the balloons 'soft' and if to a hotter place the gas will expand. If they get too hot, the expanding gas will cause the seams to split and the balloon to burst, so don't put them in a sunny window on a hot day or near heat sources such as fires, light bulbs, candles and cookers or they will burst.
Soft balloons normally revert to their original state when taken back into the warm if the difference in temperature has not been too great or too prolonged.
Keeping the balloons in an even temperature will prolong their life.
Float time
Foil balloons that have not been damaged or subject to big temperature changes, float and look at their best for 4 or 5 days, then gradually deflate over a couple of weeks. The bigger the balloon, the longer it will last (purely because it has more helium in it).
Using Balloons outdoors
If you use your balloons outside, you have to accept they might not last very long. Not only is the temperature variable, but there's wind and rain to contend with. Just a few raindrops will make a balloon droop and the wind can whip the balloon against a wall or tree before you know it.
Foil balloons should NEVER be released outdoors; they are NOT biodegradable and they can short power lines. The ribbon is a particular hazard to animals.
Summary
For maximum enjoyment, keep your foil balloons:
• away from sharp or rough objects,
• away from any source of heat,
• away from static,
• in an even temperature,
• indoors.