Why is it not permissible to hold your breath while diving with a cylinder, and what are the serious dangers resulting from this?
One of the most important rules of roller diving: Never hold your breath.
The air in the lungs expands during ascent. If you hold your breath rising, the air expands more quickly than the lungs can handle, and this may cause a pulmonary rupture.
When the air is cut off. The correct solution is to continuously exhale while ascending, not to hold the breath.
Always remember: Exhale as you ascend. There is no exception to this rule.