OP
Darkwood
The responsibility cant be put on their lap as you are the designer and installer of your work and where you cross the line in altering someone elses work then you take on the responsibilty that the previous is in compliance, what should have happened here was a risk assesment as well as an inspection of existing, that way you would have informed the customer that the existing dosn't comply and poses a potential explosion risk (if thats your findings), then you would have quoted for the necessary works to be carried out.
Having already started the works you have become responsible and the only way out if it is deemed to be an environment where explosive vapours and gases would exist is to remove any work you have done and cut your loses, if you know your customer well it may be just the case that you have a chat explaining your concerns and why you cant do the alterations they requested but either way it may make you look unproffesional, lacking competence etc in the fact you didnt bring the issue up at the beginning.
I would suggest you get a COSHH report on all products used within the paint booth, and if its the case they do pose risks of explosion then i wouldn't be touching any of the install as it exists.... the risks and liability is too high, also the very fact it seems you were originally unaware of these concerns would indicate you are not knowledgable regarding requirements and safety measures associated with these types of room which go beyong your green Reg's book.
Having already started the works you have become responsible and the only way out if it is deemed to be an environment where explosive vapours and gases would exist is to remove any work you have done and cut your loses, if you know your customer well it may be just the case that you have a chat explaining your concerns and why you cant do the alterations they requested but either way it may make you look unproffesional, lacking competence etc in the fact you didnt bring the issue up at the beginning.
I would suggest you get a COSHH report on all products used within the paint booth, and if its the case they do pose risks of explosion then i wouldn't be touching any of the install as it exists.... the risks and liability is too high, also the very fact it seems you were originally unaware of these concerns would indicate you are not knowledgable regarding requirements and safety measures associated with these types of room which go beyong your green Reg's book.