Highway 14 was closed near the Clay County line for a time Friday morning after two anhydrous ammonia nurse tanks broke free from a tow vehicle, left the highway and crashed in a ditch about a mile north of the Highway 4 East junction.
The tanks apparently were partially full of the compressed gas which turned to a hazardous vapor as it escaped from the tanks.
Some drivers attempted to drive through the gas cloud before emergency responders arrived and closed the highway.
Driving through the cloud was extremely dangerous and some motorists reported having breathing problems.
A representative of this newspaper has spoken with emergency personnel who responded to the call but the accident was still being investigated and the report was not complete.
There are several hazards associated with the gas that is commonly used as agricultural fertilizer and as a refrigerant. The following information is taken from a North Dakota State University web site.
Skin
Anhydrous ammonia causes freezing and chemical burn wherever skin and clothing are moist. The subzero temperature of escaping anhydrous ammonia freezes clothing to the body. Do not attempt to remove any clothing that is frozen to the skin. It must be thawed loose first or skin tissue may be pulled from the victim.
The caustic nature of anhydrous ammonia causes skin and tissue burns similar to burns from heat. Do not apply salves, creams or ointments of any kind to the injury. The caustic burning can be stopped only by dilution with large quantities of water.
Eyes
Eyes are continually bathed in moisture. Anhydrous ammonia will seek this moisture. The burns will result in damage to the eyes, such as cataracts, glaucoma and possibly some permanent vision loss and disfigurement.
If eyes have been exposed to anhydrous ammonia, they must be flushed with water immediately and continually and the victim must be taken to a doctor immediately. Everyone who works with anhydrous ammonia should carry a 6- or 8-ounce squeeze bottle of fresh water on their person at all times. This small amount of water will last only long enough for the worker to get to a larger quantity of water, but it may make the difference between blindness and sight.
Initially, forcing the victim's eyelids open after the exposure may be necessary. The ammonia trapped under the eyelids must be flushed out with water or it will continue to burn the eye and related tissues.
Lungs
At low concentrations, the odor of anhydrous ammonia usually will drive the unprotected worker away from the scene. At a higher level of concentrati, the worker may not escape without inhaling a dangerous dose. The entire respiratory system is very moist, so anhydrous ammonia will be attracted naturally to that part of the body. When a concentrated level of anhydrous ammonia is inhaled, it will burn the respiratory system quickly. The victim may hurt too much to breathe. The respiratory system essentially may be paralyzed by the pain.
First-response rescue workers may not be able to treat a serious inhalation exposure. Medical technicians may be able to administer oxygen to aid breathing after their arrival on the scene Maintaining adequate respiration for the victim until delivery to a medical facility may be difficult.
Respiratory protection is extremely important, but also limited in what equipment is available. A two-cartridge respirator is effective only for exposure levels of less than 300 ppm. Canister type respirators may be effective for longer periods at higher concentrations, but without skin protection, walking through an ammonia cloud is generally not advisable. A self-contained breathing apparatus (SCBA), which supplies the air to be breathed, and a sealed, protective hazmat suit are required for working in a cloud of escaping anhydrous ammonia. Anything less will not sufficiently protect a person in this situation.
First Aid
Start first aid treatment immediately when someone is exposed to anhydrous ammonia. The chemical burning starts instantly and the injury becomes worse as time passes. Treatment consists of flushing the affected body area(s) with large quantities of water.
One short flushing is not sufficient. Maintain a steady flow of water over the affected area(s) until the victim is delivered to medical help. The water provided with each nurse tank or other container will not be enough. Five gallons flowing in a pencil-sized stream will last approximately seven minutes.
Additional water should be carried on every tractor used in field applications and in every field support motor vehicle. Collect as much water as possible and continue flushing while arrangements are being made to transport the victim to a medical facility. Do not reuse the water; it will not provide relief, having already absorbed anhydrous ammonia.
Make arrangements to transport the victim to a doctor or hospital immediately after exposure. First aid can be given while transport arrangements are being made, but get the victim to medical care as soon as possible. Notify the hospital that the victim is being transported. First aid flushing should be continued while in transport.
Uncontrolled Releases
Clouds of anhydrous ammonia are subject to the unpredictability of air movement; they will change direction as quickly as the breeze. Clouds of ammonia may be nearly invisible in some atmospheric conditions, but they appear as white clouds when the atmosphere is damp. Rain will absorb the ammonia and remove it from the air.
Anhydrous ammonia is heavier than air and will settle in the low areas of the surrounding landscape, such as road ditches, sloughs and valleys. People in threatened areas must be warned of the release and advised to leave the area until the release has been controlled and the area is considered safe for re-entry. Animals and livestock should be removed from the threatened area after people have been taken care of first. Most animals will do their best to leave the area long before ammonia concentrations become strong enough to cause them much discomfort.
Because of the seriousness of exposure to anhydrous ammonia, personal protective equipment must be well-maintained. This includes unvented goggles; rubber gloves; respirator; heavy-duty, long-sleeved shirt; and long pants.
The goggles and gloves are to be kept in a safety equipment container mounted on each nurse tank and be accessible from the ground. Having another set readily available on the tractor is an excellent idea. Suitable gloves are made of rubber and are impervious to ammonia, and have long cuffs that should be turned back to prevent drips from running down the arm when hands are elevated. The fit should be loose enough for easy removal but snug enough for good protection.
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