On 12 November, 44 of the 46 registrants of the webinar "Beirut explosion: How does ammonium nitrate behave in a fire and how powerful was the explosion?" logged in for this online meeting. After an introduction by our chairman Jan Wind and an introduction to the presentation by board member and initiator of this webinar Bart Koene, it was Prof Hans Pasman's turn. He had optimally prepared his presentation by recording it in advance so that during the webinar this film could be shown in one go. it turned out to be a more than interesting account of the possible scenarios that could have played out in Beirut. Substantiated as much as possible by data coming from different sources and with a lot of facts about the special substance 'ammonium nitrate'.

Shortly after 9 pm, the presentation was finished and the questions - which had been asked by chat in the meantime - were carefully gone through one by one. At half past 10, Jan Wind closed the webinar while we were almost a trending topic on Twitter in the meantime.

That ammonium nitrate (AN) should be protected from fire is well known and various regulations exist. Several times it has been shown that in a fire in large-scale storage of AN, it can come to detonation with horrific consequences.

Exactly how this occurs has never been fully reproduced under controlled conditions despite much research. The few weeks available to find this out from many sources was quite a challenge, while in addition, for safe distances, given the amount at storage, information on the strength of an AN detonation compared to the explosive trotyl is important. This information was derived in three different ways: shock wave velocity, damage image and crater size.

Hans Pasman will present online details on the storage conditions of ammonium nitrate and outline a possible Beirut detonation scenario with an analysis of the strength of the detonation. You will receive the link to participate shortly before the webinar.