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EN 12845

Ordinary Hazard Group 4 (OH4)

EN 12845 classification for textile manufacturing, woodworking, tobacco, tyre manufacturing.

Definition

OH4 is the highest Ordinary Hazard category: 5.0 mm/min density over a 360 m² area of operation. Most occupancies that would qualify for OH4 are now classified as High Hazard Process (HHP) because of EU insurer practice.

Referenced in

  • EN 12845

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Generate a compliant sprinkler layout, run the hydraulic calculation and export a priced bill of materials — checked against EN 12845 and NFPA 13.

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