Moto850,
Did you perform due diligence?
If your booth is in Canada or the US, then it needs an automatic fire extinguishing system.
Your least expensive option is to install a pre-engineered dry chemical automatic fire extinguishing system meeting the requirements of 2006 International Fire Code Section 1504.4 which requires compliance with NFPA 17.
Based on your posting history, I suspect your not an engineer and your sponging for free consulting. I'm not playing. Good luck, stay safe, and be careful. Spray finishing is a hazardous process.