Design a bespoke Flammable Storage Cabinet

We are looking to design a flammable storage cabinet which is an adaption of something on the market already to suit a particular aplication in the industry we supply.
We have seen an example at a customer who have made it themselves.
It is a basic 'bin' style cabinet but needs some sort of lip between the bottom and hinged lid to make it flame proof.
The chemicals stored inside are highly flammable so the idea is if there is a fire, the operator can slam the lid and contain the fire.
The cabinet will be approximately 1000mmx 300mm and 450mm high in total.
It will have a hinged lid and in side a shelf in which things will slot. These will be buckets and aerosol cans.