unless the small one is electric there would be some fumes in that confined space. no mask. Probably done it many times: bit like spraying glyphosate= very safe till it kills someone. A couple of cubic metres(yards) of wood there= at least a couple of tonne(ton). At least the ground is level! I use a pallet jack inside my storage container and I can snug up the double up pallets (I made the box like pallets myself & they lock together) but it leaves a bit to be desired.