The production area is classified as the area of plastic production and processing. In the mentioned area there are K160 sprinklers installed. Ventilation round ducts are installed below, which are an obstacle to the flow of sprinklers. It is necessary to use sprinklers under these ducts but my question is – do we need to use solid barrier installed on a horizontal plane below round ducts – as it is written in the 18.104.22.168.7 NFPA13 - "Sprinklers installed under round ducts shall be(...) shielded from the discharge of overhead sprinklers."?
Additional question is – should we in similar situation but in a warehouse with ESFR sprinklers use barriers (as it was written before) below round ducts?
Thank you in advance for your help.