Updating ammonia dispersion models

Research is underway in order to improve existing ammonia-dispersion behaviour models.
Ammonia is increasingly used as an alternative refrigerant as it is energy efficient, has no detrimental effect on the climate or on the ozone layer, but is toxic and can be explosive under certain specific conditions.
However, it is very difficult to assess the consequences of an accidental leak of pressurized liquid ammonia, because of the large number of physical phenomena involved (flash, rain-out, evaporation, impact behaviour on obstacles, etc.) and research is under way in order to update current models. For instance, French Ineris (National Institute of Industrial Environment and Risks), claims it is now treating over a million raw data gathered from medium-scale tests commissioned by the French Ministry of the Environment, and hopes to better understand the complex phenomena involved when leakage occurs and to redefine safe distances.
The test bench involved 80 thermocouples, 5 pressure sensors, 13 gas detectors, 2 scales, several cameras, etc. Around 20 ammonia-rejection tests, following various scenarios, and each with hundreds of continuous measurements were carried out, involving the skills of around 20 engineers and technicians.