Having just got back to the lab and met with the contractors they have managed to short term fix the extraction fault. This means that the clean labs and multi collector lab is back up and running. 

They will have to access the fan unit on the roof to change the faulty switch which will require a roof shutdown (lab shutdown) but this will be at a time convenient to us, chemistry and MDI in the future.

Please feel free to carry on as planned :)

Cheers,

Edward