|SNMG1 unit HNLMS Tromp testing the pre-wetting system. This system protect the ship against Nuclear, Chemical and Biological adverse environment. [source: https://www.facebook.com/media/set/?set=a.999409840078619.1073741865.559878640698410]|
Haven't seen such a NBC system before. Did a quick search; seems it's a water sprinkler system to be activated in the event of a imminent NBC attack.