Recommended Evacuation Distance for Offsite Risk Assessment of Ammonia Release Scenarios

냉동, 냉장 시스템에서 NH3 누출 사고 시 장외영향평가를 위한 피해범위 및 대피거리 산정에 관한 연구

  • Received : 2015.11.16
  • Accepted : 2016.06.16
  • Published : 2016.06.30


An accident of an ammonia tank pipeline at a storage plant resulted in one death and three injuries in 2014. Many accidents including toxic gas releases and explosions occur in the freezing and refrigerating systems using ammonia. Especially, the consequence can be substantial due to that the large amount of ammonia is usually being used in the refrigeration systems. In this study, offsite consequence analysis has been investigated when ammonia leaks outdoors from large storages. Both flammable and toxic effects are under consideration to calculate the affected area using simulation programs for consequence analysis. ERPG-2 concentration (150 ppm) has been selected to calculate the evacuation distance out of various release scenarios for their dispersions in day or night. For offsite residential, the impact area by flammability is much smaller than that by toxicity. The methodology consists of two steps as followings; 1. Calculation for discharge rates of accidental release scenarios. 2. Dispersion simulation using the discharge rate for different conditions. This proactive prediction for accidental releases of ammonia would help emergency teams act as quick as they can.


ERPG-2;gaussian plume model;EFFECT 9;ALOHA;PHAST ver 6.7;ammonia


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Cited by

  1. Analysis of Impact Zone of Quantitative Risk Assessment based on Accident Scenarios by Meteorological Factors vol.39, pp.12, 2017,


Supported by : 한국연구재단