4 Suitability for use on fire/smoke doors Grade 0: Not suitable for use on fire/smoke resistant door assemblies Grade 1: Suitable for use on fire/smoke resistant door assemblies (EN 1634-1) 5 Safety Grade 1: All hinges are required to satisfy the essential requirement of safety in use. Therefore only grade 1 is identified 6 Corrosion resistance According to EN 1670 Grade 0: 0 h (No defined corrosion resistance) Grade 1: 24 h (Mild corrosion resistance) Grade 2: 48 h (Moderate corrosion resistance) Grade 3: 96 h (High corrosion resistance) Grade 4: 240 h (Very high corrosion resistance) 7 Security-burglar-resistance Grade 0: Not suitable for use on burglar-resistant door assemblies Grade 1: Suitable for use on burglar-resistant door assemblies, subject to satisfactory assessment of the contribution of the hinges to the burglar-resistance of specified burglar-resistant door assemblies 8 Hinge grade Fourteen grades of hinges are identified in this European Standard, as listed in the table Fourth digit Fifth digit Sixth digit Seventh digit Eighth digit Fire/smoke suitability Safety Corrosion resistance Security Hinge grade Grade Grade Grade Grade Grade 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0, 1, 2, 3, 4 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 0 or 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14