Historical
DIN EN 981/A1:2008
Safety of machinery - System of auditory and visual danger and information signals; German version EN 981:1996/prA1:2008 (Foreign Standard)
The document is applicable to all kinds of danger signals. For cases when light signals are to be used complementary to sound signals, characters are stated for both. The signals shall be clearly perceived and differentiated.
Deutsches Institut für Normung [din]