Symbol 2685 from ISO 7000 - Title/Meaning: Fire alarm Function/description: To identify the equipment (manual call point) used to manually activate a fire detection and alarm system.
pay attention to orientation of symbolAdditional information: 
May be used in combination with the symbol for ""pressure"" (ISO 7000-1701) to indicate that the frangible element on the equipment needs to be displaced by the application of pressure. May also be used in combination with the symbol for ""manual activation control"" (ISO 7000-2684) to indicate that a separate control is activated after the fangible element is displaced.
Own work using: iso.org/obp/graphics/grs/ad2a4997-d07a-4aa0-8841-1b8a012a72da 200.png
Vectorization:  Mrmw