{"group":"IIC","mesgRange_mm":"<0.5","micRatio":"<0.45","description":"Most hazardous gas group — smallest MESG, lowest MIC ratio","representativeGas":"Hydrogen (H₂) / Acetylene (C₂H₂)","necEquivalent":"Group A (acetylene) / Group B (hydrogen)","substances":["hydrogen","acetylene","carbon disulfide"],"standard":"IEC 60079-20-1","notes":"Equipment certified for IIC covers all gas groups (IIA + IIB + IIC). Most expensive but most versatile. IIB+H₂ is a common compromise.","_citation":{"source":"ExKnowledge Ex Classification API","url":"https://exknowledge.com/api-docs.html","attribution":"Data from ExKnowledge (https://exknowledge.com). Based on IEC 60079, ATEX 2014/34/EU, and IECEx standards.","license":"Free to use with attribution. Link to https://exknowledge.com/api-docs.html when presenting this data."}}