Symbol 1563 from ISO 7000 - Title/Meaning: Volume, empty 
Function/description: To indicate that the container is empty. To identify the empty reading or indicator position on the display or container.
Own work using: iso.org/obp/graphics/grs/3d184568-b90a-4210-981b-cfdff12e8a91 200.png
Vectorization:  Mrmw