Case study: Anhydrous spill in Northern Illinois

A large-scale anhydrous leak happened in Illinois a few days ago, so I thought I’d use it as a case study. The information available in the original article is pretty limited, but even so I can see a few areas where prevention and response strategies could have been improved, as well as a few areas where people were taking precautions and responding appropriately.

Here is a quick summary of what happened:

-A farmer was pulling anhydrous with a tractor around 4:30 AM. As he drove down the road, a hose sprang a leak

-When firefighters responded, they thought it was just a car fire and weren’t wearing protective equipment or take precautions against chemical exposure initially

-as this was happening, people were driving through the gas and were having difficulty breathing. One driver even went off the road

-the area was heavily populated so people in their homes were also exposed

-In total over 40 people were taken to the hospital by ambulance, and many more drove themselves in.

Some things that went right:

-The driver of the tractor didn’t try to deal with the leak himself, and got out before he was seriously exposed.

-The driver of the tractor was moving anhydrous very early in the morning. Moving equipment, especially something as dangerous as anhydrous, during off-peak hours helps reduce the risk of crashes and the risk of people being exposed to the anhydrous in the event of a leak. This is especially important for heavily populated areas like where this leak happened.


-Someone called the fire department right away. No one tried to stop the leak on their own.

-Once the fire department figured out what was going on, they shut down roads, ordered residents within a 1 mile radius to stay indoors, performed evacuations, and performed wellness checks. In other words, once they figured out what they were dealing with, they took proper precautions to minimize people being exposed.

Some things that could have been improved:

-The fire department didn’t realize this was an anhydrous leak initially. The fire department should have known to look out for anhydrous if they get a call involving farm vehicles this time of year. Getting firefighters into the proper protective equipment right away would have prevented the most serious exposures, and getting the road closed and people inside earlier in the process would have considerably reduced the total number of people exposed.

-Drivers also didn’t realize this was an anhydrous leak and drove into the gas cloud, and at least one driver was going too fast to stop in time to avoid driving into the gas. So many on-road incidents happen because the drivers of passenger vehicles don’t know how to adjust their driving around ag vehicles or what the hazards might be. I’ve already seen a slew of public service announcements for drivers in the aftermath of this incident, but I wish there was more driver training and more drivers getting pulled over and ticketed for illegally passing ag vehicles.

-One thing I’d want to check is if the anhydrous equipment was being inspected regularly and properly, especially since we’re at the beginning of the season. Inspections won’t catch everything, but they go a long way towards preventing leaks.

All in all, it sounds like everyone who was involved is going to be OK, which is impressive considering the size of the leak and that it happened in a busy neighborhood. Still, if firefighters and drivers were more aware of the potential hazards and had been able to start responding to the situation correctly more quickly, the number and severity of exposures could have been dramatically reduced.

Here is a link to the original article:

https://www.kenoshanews.com/news/local/anhydrous-ammonia-causes-massive-hazmat-response-in-illinois-hospitalized/article_e64a7017-6730-58d2-b42c-742c6c6a0727.html?fbclid=IwAR1tdthlBf8Orzm_I7fILBart1857x8WbsAN5eSaoxyc7UnoavXhZrFDTjk

Video:Anhydrous Ammonia Field Safety

To go with our series on spring safety I thought I’d share this video from the Ohio Extension. OSU has one of the best ag safety programs out there and they make some great videos, so if you have time I’d recommend browsing through their Youtube channel. There haven’t been any reports in the database related to anhydrous yet, but I know a few people personally who have had close calls over the years.

With anhydrous, personal protective equipment is very important. Several of the close calls I know of easily could have been serious injury if the person involved hadn’t been wearing the proper protective equipment. Investing in goggles or ideally a full-face mask is a good idea since anhydrous can do a lot of damage to eyes very quickly. (As a side note they’re also amazing if you have bad allergies like I do and need to deal with mold or mow ragweed) I’m including a link to one of the nicer kits I found online. It’s a little bit more expensive, but it looks like it comes with several cartridges and a storage case. The case is important because it keeps dust and debris out of the mask and because less air flowing through the cartridge, the longer it will last. If you get a mask that doesn’t come with a case, definitely store it in some kind of container to help make it last as long as possible!

Here is the respirator link:

https://www.globalindustrial.com/p/safety/breathing/cartridge-respirators/anhydrous-ammonia-respiratory-kit-sr-200

Also remember that anhydrous is flammable, explosive, and forms corrosive solutions when mixed with water. Carrying several gallons of water is recommended in case a person comes in contact with the anhydrous, but if a fire happens it’s best to leave the area and call in the professionals due to the explosive potential. This is especially true if a fire happens near a storage area.

If you’d like some additional information, I’m including links to a more detailed safety article and to the CDC’s hazardous materials sheet for anhydrous at the bottom of the page. If you can deal with the super technical writing style, the CDC hazard sheets are really great for learning about the hazards of almost any chemical and how to avoid them. Enjoy the video!

Here is the link to a more detailed article:

https://articles.extension.org/pages/63196/anhydrous-ammonia-safety

And here is the link to the CDC hazardous materials sheet:

https://www.cdc.gov/niosh/ershdb/emergencyresponsecard_29750013.html