I am searching on behalf of a lab that does a significant volume of fundamental organic synthesis. As a result, they need to store so many 4-L bottles of flammable solvent near their work space that they are using the acid storage cabinets for flammables. (Under each hood there is one acid storage cabinet and one flammables storage cabinet.)

The acid storage cabinets are distinguishable by the vents on the doors and the PTFE lining of the walls and floor inside the cabinet. The flammables storage cabinets are designed with no vents (specifically on the cabinet doors) and ~1" of material mounted in a metal sheeted case on each side of the cabinet, presumably something flame resistant or retardant. So I am wondering if others have experience with a conversion of this sort. (Replacing the whole cabinet would be excessively disruptive and cost prohibitive.)

For example it is it within acceptable practice to just replace the doors to the cabinet so that flammables storage does not have vents? Or to be up to fire code, would one be required to also change the lining of the cabinet (also prohibitive)?

Thanks for any experience on this matter you might be willing to contribute,