In Scenery volumen are represented by Volumen nodes. But unlike regular meshes those volumes are not rendered directly but together at the same time. This is coordinated by the VolumeManager which is hubable and a Node at the same time.
The sampling of each volume is done in the same shader. The shader is auto generated and specific to the amount and type of used volumes. Therefore, adding a volume may trigger a shader rebuild which automatically handled by the framework. For more see Volumen Shader and Uniforms.
NOTE: The scene graph subtree below a Volume node is scaled by the dimensions of the volume. Example: To move a sub node to the position of the voxel at (20,120,49) set its local position to (20,120,49).