All chemical containers need to be labeled with the name of the chemical at minimum.
You need to bet a folder or 3-ring binder to put all of the chemical MSDS in there and it needs to be within reach of the driver at all times. In case of an accident, the HAZMAT team will find it and determine how to handle the cleanup if you are unconscious if there is a chemical spill.
I usually use the 5 or 3 gallon buckets with GAMMA SEALS (screw top lids) that adapt to regular buckets. They have a big rubber gasket so they do not let air in.
I would not keep them in the original bags because with one little tear, moisture will get in and the powders start to clump and sometimes get very hard.
You could use regular buckets that have tight fitting lids but usually after you break the tabs to open it, they do not stay on very good.
I know a couple guys that use the large pet food containers for their powder chems and put a label on them.