The Compressed Helium Gas sign is used to let people know that there is a special gas called helium in a container that is compressed or squeezed together. It is important to have a sign for this because helium gas can be dangerous if not handled properly.

The sign is usually put up in places where compressed helium gas is stored or used, like in science laboratories or places where they fill up balloons with helium. These places need to take extra precautions because the compressed gas can escape and cause harm.