You need something like this. Mine is lockable with individual full height compartments made from wood, specifically 7/8" blockboard sides and 3/8" top and bottom. There is a guideline for it, I will see if I can find a copy
/d
Du lytter aldrig til de ord jeg siger. Du ser mig kun for det tøj jeg har paa ...
I might be worthwhile checking what the latest spec needs to be. I was informed, by my FLO, that the sides need to be at least 20mm thick ply, not 18mm as stated in the blurb that I had at the time. Some forces insist that it also has to be chained to the wall (something the the Fire Brigade around here dont like you to do!)