she told me hazmat stuff was routinely packed at the bottom of the pile as standard procedure.
There is actually a small degree of sense in this.
Not GOOD SENSE, and not well thought out, but a small amount of sense, if you consider that generally speaking, when something leaks, gravity pulls the material DOWN. SO a leaking package on the bottom of the pile is less likely to interact with the items above it.
BUT, putting weight on top of a package of hazardous chemicals is STUPID, and INCREASES the risk of damage. Also, while liquid will travel down, vapors travel UP.....or down if heavier than air. And flames can go both ways as well.
I asked her if she any idea what was in the box and what would happen if it got exposed directly to water. She said she didn't have the slightest idea. I'm sure nobody did along the entire shipping chain.
Somebody in the shipping chain DID know. Everybody in the shipping chain could have known, and has the legal right to know. By law, companies must have and make accessible the MSDS sheets (or whatever acronym is in curren use) Material Safety Data Sheets, which identify the hazards of the material's chemical components. Worker Right to Know, its in the CFR and some other places.
The fact that most workers don't bother finding out, or in some cases don't even know how to is a different matter.
Nothing like spending hours or even DAYS responding to the complaint of a "barracks lawyer" type over the wrong MSDS because the bag of floor sweeping compound he had said "Clean up IV" and the MSDS just said "Clean UP" as the product name....
Things can get on the Hazardous list by containing a known, or SUSPECTED carcinogen. And some things are the lists only when provided by the employer but not when naturally occurring. Silica sand dust, is a listed item, requiring worker right to know, when the company buys it, (for sand blasting, or for sanding the road in the winter) but not when it blows in on the wind from the 500 square miles of desert surrounding the plant....
TABLE SALT would be on the hazardous list, because of its chemical composition, but its not, because it is listed as a "food item".
Few people who's jobs do not directly involve the labyrinthine morass of chemical shipment and storage regulations have any clue about them at all, and fewer still care about what doesn't directly impact them, day in and day out.
A bit like gun control in that regard, people who don't own, use, deal with guns generally don't give a rip what the gun control laws are....until it personally affects them...