Phosphine is used in making home signals and for making smoke screens.
Signals use to indicate danger point to steamers in deepsea and ocean are called holme signals.
- A mixture of calcium phosphine (ca3p2) and calcium carbide is placed in metal containers and dropped in water then ca3p2 and calcium carbide react with water producing phosphine(ph3) and few amount of di-phosphine (p2H4)and acetyline (c2H2).
- Di-phosphine sponteniously catches fire and also makes acetyline to burn.
- The flame thus produce , acts as signal to approaching ship.