Good Morning. I have came across this Electrical Installation Container which is situated inside the main hall of a factory. The container has smoke detection and a FD60 fire door. However, there are 2 large extraction fans built into the roof. They just blow directly into the main hall and have no ducting attached. 

Should the fans be connected to ducting with fire dampers installed close to the fan? 

My concern is compartmentation of the container and the smoke/heat/products of combustion that would freely exit into the main hall through the 2 ventilation fans. The fans are mounted in a square opening approx 600mm x 600mm.

My thoughts. To recommend the installation of fire rated ducting that rises approx 500mm above the container roof. Above the fan and within the ducting an intumescent grille with dimensions of 600mm x 600mm. 

Would you agree this is suitable?

Is the main hall provided with smoke ventilation?

Hi Anthony,

No, there is no smoke ventilation within the main hall. There is a HVAC system to blow cold air into the main hall when the temperature gets too hot for the workers. This is activated manually. 

I agree with you there should be smoke and heat fire dampers fitted because whats the point of fitting fire doors if you are accepting two 600mm2 holes in the roof of the container assisted by fans.

Thanks for confirming my initial thoughts Tom.  I did go ahead with the recommendation.