My first reaction was being horrified that this accident happened relatively near me (or at all). My second reaction was being horrified that nearby schools were being locked down because of fear of nitrogen in the air.
You scoff, but has anybody tested the air?!? I bet there are shockingly high levels of nitrogen in the air near that plant!
Did the school officials and emergency response teams know that it was a nitrogen leak?
Or did they just know that something was wrong in the area and that workers were injured?
If the latter, it makes sense to take precautions until they know what’s going on.
I admit when I first read the OP I though “…and how many chickens died?” but after reading the article I’m assuming the chickens arrived at the facility already deceased and ready to be disassembled.
Curious if all the injuries were asphyxiation or if some involved “thermal injuries” i.e. frostbite or the like.
Yeah, I’m morbidly curious.
But I am feel sympathy for the injured, the deceased, and their families. Everyone goes to work expecting they’ll be going home later in the day, safe and sound. It’s tragic when it doesn’t happen that way.
I confess to wondering the same but air displacement is probably more likely.
Liquid and pure gaseous nitrogen are very dangerous in confined spaces, and by some estimates have killed more people in occupational accidents than any other caustic or toxic gas.
I would assume that school officials acted as indicated because the source and type of gas had not been verifiably identified. An ammonia leak, for instance, could be highly toxic and in sufficient concentration could overtake people before they had a chance to flee the area. Children are particularly vulnerable to airborne pollutants so taking precautions is sensible even if it seems like an ignorant overreaction in hindsight.
Stranger
It sounds like they knew what it was all along.
I was thinking of full on science class, rose-shattering type of terminator 2 deaths.
If there’s a major leak of toxic gas in the neighborhood (think: Bhopal) would a locked-down school be air-tight enough to be any help?
Depends on the gas, I would imagine.
If it’s a gas that’s toxic in very, very small quantities probably not.
Also depends on the amount, as any gas that can displace oxygen will be fatal in great enough amounts.
Whether or not it’s heavier than oxygen might also matter - if it’s denser it will hug the ground, in which case evacuating to higher floors in a building might be a wise move. Unless something like wind is stirring up layers of air.
So… type of gas, quantity, proximity to the school, density, weather, and probably other factors come into play.
Probably in the high 70% range.
Once the nitrogen cloud dissipates then yes, it’s no problem, but if you got caught in the nitrogen cloud before it dissipated, you could pass out in a matter of seconds from the lack of oxygen, and the extreme cold of the nitrogen gas could cause fatal damage to your lungs.
When you have a leak/spill that big, it takes a while for the nitrogen cloud to dissipate. Keeping people away from the cloud is actually a pretty smart thing to do.
Is there any indication that the spill was big? Big enough to kill in a confined space is one thing, but a cloud big enough to be a risk to people thousands of feet away? That seems to be whole orders of magnitude removed.
Given the number of injuries and deaths and how many people were taken to the hospital for respiratory issues, it seems pretty obvious to me that this wasn’t just a minor leak. This was a big leak/spill.
I’m comfortable with erring way, way on the side of caution with a hazardous chemical spill when it comes to both the general public and a school full of children. Think of it less as an “over-reaction” and more of an “unplanned drill”.
This incident brought back to mind bit of news (NASA techs killed by vented nitrogen):
March 19, 1981: Shuttle Columbia's First Fatalities | WIRED.
Local news article suggests at least one fatality was temperature-related, but I’d be surprised if some weren’t asphyxiated by the gas.
I suppose I’ll just have to let it go.
oof. 
I want you to think about what you’ve done, young man.
And change your behavior, or Elsa there will be consequences.
Big industrial refrigeration systems commonly use ammonia as the refrigerant. If there’d been a big refrigerant leak at the plant where I worked, it would have wiped out half the suburb.
I don’t think that locking the kids in their class rooms would have helped.