well apparently it was in a silo [ as pics show ] that was full [ part?] of recycled bio waste ready for further use! for the "minimal" damage caused, all be it deadly the explosion said to rocked building 200m+ away must of been in gas form? [ although contents may have been in form of solids ] Having done a number of exams in dangerous goods/ explosive materials, the ullage factor may be the cause of the "fuel" …