We have a 4 1/2 inch slab on metal decking between floors. We are installing 3/4 inch PVC conduit in slab to penetrate down through the metal deck for lighting. Do we need to fire stop around the conduit as it penetrates the metal deck to maintain the fire rating of the fire rating of the 4 1/2 inch slab". I attached a detail.
Hello,
Typically we treat lighting in ceilings with a 5 sided gypsum box enclosure and we treat the electrical conduits penetrating through the box enclosure with sealant.
In you drawing it appears the electrical conduits have been cast into the concrete.
I recommend submitting for an engineering judgement so we can understand the full condition.
You can submit for an engineering judgment by filling out the form I have attached and emailing it into usfirestopeng@hilti.com, please also include any pictures or sketches of the condition that could be useful for our understanding.
We do not have any UL systems that will work for this condition so the fire rating will need to be evaluated in an engineering judgement.
