Is the effect of nitrous oxide stronger if you keep your nosed closed?

The effect of nitrous oxide is NOT stronger when you close your nose. It doesn’t matter at all for the effect. However, the risks are increasing. Laughing gas is compressed in the whipped cream cannister and then expands when it is released. Because this volume has nowhere to go, the pressure increases in your head. This can lead to inflammation in the head or even to the bursting of the eardrum.