Symbol 6353 from IEC 60417 - Title/Meaning: Protection against the thermal effect of the electric arc Function/description: [To indicate ; - the suitability of equipment for electrical arc protection; - the electric arc protection level provided, such as thermal, mechanical projections.]
Additional information: 
This symbol should be used in the orientation shown.
The use of this symbol is specified, for example in IEC 61482-2 for protective clothing against the thermal hazards of an electric arc, and in addition for future products of face-shields, helmets, gloves and footwear. This standard requires to have the number of the IEC standard and the protective level expressed in:[ - (arc rating) ATPV = XX cal/cm 2 and/or EBT = XX cal/cm 2 and/or ELIM = XX cal/cm 2 (incident energy limit) - and/or APC=X (arc protection class = 1 or 2)]immediately adjacent to the symbol.
Own work using: iso.org/obp/graphics/grs/307614ac-19a1-4f47-a7b6-147799d866d7 200.png
Vectorization:  Mrmw