Why Does Helium Change Our Voice?

Who would have thought that the gas inside a balloon, can change your voice? The gas that can send balloons to uncharted heights, can send your voice into uncharted pitches too. Let’s see why?

What is helium?

Helium is a very light gas, bested only by hydrogen. However, helium is neither as reactive or explosive as hydrogen. Naturally, it is the first choice gas to fill up balloons. When I say balloons, it is not just the ones you see at a birthday party. Scientists who study weather and climate send balloons into a higher atmosphere too, and guess what they fill their balloons up with? Helium.

Scuba tanks must be full of oxygen, after all, divers need that extra bit for a nice dive. Not so much. Scuba tanks have 80% helium and only 20% oxygen. Helium is non-toxic, does not cause respiratory troubles, and is inert. Safe to say, helium makes no chaos in our body and is thus used with oxygen.

Also, most stars have some amount of helium present in them. This gas has been to every nook of the universe it seems!

Why does helium change our voice?

When you speak, your vocal cords vibrate to produce sound waves. These sound waves travel through the air and into our ears, allowing us to hear your voice. But the way your voice sounds depends on the speed at which sound waves travel. In normal air, which is a mixture of gases including nitrogen and oxygen, sound waves travel at a certain speed.

Helium is much less dense than the air we breathe, which means that sound waves travel through it much faster. Generally, sound travels 2.7 times faster in helium than in air. When you speak with helium in your lungs, the sound waves produced by your vocal cords travel through the helium much faster than they would through regular air. This increase in speed causes your voice to sound higher and squeakier than usual.

There is a bit of myth-busting that is needed too. You might have heard that sound travels faster through solids and in liquids than in air. The question arises, how come helium is less dense, but sound travels faster through this has and not through air? As it turns out, sound travels faster in water and through solids, only because they are much more rigid than air– the molecules are closely packed. In the case of air and helium, both of them are gases and are equally stiff. And you’ve probably guessed it, helium cuts it in the “sound race” because of it’s lower density.

Is this dangerous?

It’s important to note that while inhaling helium occasionally for a few seconds can be a fun and harmless activity, doing it too much or for too long can be dangerous. Helium displaces oxygen in your lungs, which can lead to oxygen deprivation if done excessively.

The next balloon at a birthday party might as well become the source of a cool party trick. But, as always, safety comes first.

Glossary

Helium: A chemical element with the symbol He and atomic number 2. It is a colorless, odorless, and inert gas, often used for various purposes, including filling balloons.

Inert: Not readily reacting with other substances; chemically inactive.

Respiratory Troubles: Problems related to the respiratory system, which includes the lungs and airways.

Sound Waves: Vibrations that propagate through a medium (such as air, water, or helium) and can be detected as sound.

Density: The measure of how much mass is contained in a given volume of a substance.

Oxygen Deprivation: A condition where the body lacks an adequate supply of oxygen, which can be harmful or even life-threatening.