Despite attention in recent years to laws regarding its transport, application, and storage, anhydrous ammonia remains a serious health risk for Iowa farmers. According to the Iowa Department of Public Health, 55 Iowans were injured in accidents involving anhydrous ammonia between 1990 and 1992. Nineteen injuries required hospitalization for burns, loss of eyesight, and respiratory problems.
This publication will look at common ways Iowans are exposed to anhydrous ammonia and how to avoid these situations, its properties and first aid treatment, as well as Iowa regulations regarding its transport.
Most deaths from anhydrous ammonia are caused by severe damage to the throat and lungs from a direct blast to the face. When large amounts are inhaled, the throat swells shut and victims suffocate. Exposure to vapors or liquid also can cause blindness.
An additional concern is the low boiling point of anhydrous ammonia. The chemical freezes on contact at room temperature. It will cause burns similar to, but more severe than, those caused by dry ice.
Under normal temperature and air pressure, anhydrous ammonia is a colorless gas. However, anhydrous ammonia is used and transported under pressure as a liquid. All equipment used for applying or transferring liquid anhydrous ammonia must be designed for use under high pressure to avoid ruptures or breaks.
Anhydrous ammonia has a distinct odor, which humans can detect in concentrations as small as 5 parts per million (ppm). When used in fertilizer, anhydrous ammonia has a concentration of about 1,000,000 ppm. Brief exposure to concentrations of 2,500 to 6,500 ppm can result in death.
Always wear ventless goggles or a full-face shield, rubber gloves with a long cuff that can be rolled to catch drips, and a long-sleeved shirt. Non-rubber gloves made of ammonia-proof materials also are acceptable. Never wear contact lenses around anhydrous ammonia because the lenses collect the chemical and intensify caustic effects.
Always carry a personal water supply in a squeeze bottle to use for instant first aid. The bottle should contain 6 to 8 ounces of clean water and be within arm's reach at all times. At least five gallons of water should be accessible within several seconds.
The best first aid treatment for anhydrous ammonia exposure is water -- large amounts of it. Flush all exposed areas with water for at least 15 minutes.
If the nose or throat is exposed, flood the area repeatedly for 15 minutes, being careful not to choke the victim. Even a brief or mild exposure to the eyes requires irrigation for a minimum of 15 minutes. Remember to flush underneath eyelids.
Always begin flushing immediately. This reduces injuries, caused as soon as anhydrous ammonia contacts skin or clothes. If water is not immediately available, use any non-toxic liquid such as cold coffee. Orange juice and other mildly acidic liquids will help neutralize the chemical. Water from a nearby farm pond also can be used until other water supplies are available.
Even with proper first aid, seek medical help as soon as possible. Explain the source of the injury so that medical providers will not apply oils or ointments. This treatment intensifies damage from burns.
If you find someone in a continuous stream of anhydrous ammonia, do not attempt rescue without proper equipment. Rescuers must wear a self-contained breathing apparatus (SCBA) and protective clothing.
Always take care in removing a victim's clothing. Clothes could be frozen to the skin and removal could cause additional injury.
You also must display the slow-moving vehicle (SMV) emblem if you're traveling at speeds less than 25 miles per hour. At higher speeds, remove or cover the emblem. In Iowa, speed limits are determined by the rating marked on the nurse tank tires.
It's important to understand the dangers of anhydrous ammonia. Operators should know and understand all procedures, usually provided by the chemical dealer, before they begin anhydrous ammonia application. Better yet, operators may want to consider hiring a professional to perform this dangerous job.
ANHYDROUS AMMONIA SAFETY
See answers at the end of "What Can You Do?".
What Can You Do? You can reduce your risk of exposure and reduce injuries in these ways:
Answers to quiz:
1-c; 2-True; 3-False; 4-False; 5-a, b, and c.
FOR MORE INFORMATION
Publication #: Pm-1518d
This Fact Sheet is apart of a series from the Safe Farm Program, Iowa State University Extension, Ames, Iowa. Safe Farm promotes health and safety in agriculture. It is funded by the National Institute for Occupational Safety and Health, Iowa State University, and a network of groups that serve Iowa farm workers and their families. Publication date: April 1993.
Prepared by Charles V. Schwab, extension safety specialist; Mark Hanna, extension agricultural engineer, and Laura Miller, extension communications, Iowa State University Extension, Ames, Iowa
Disclaimer and Reproduction Information: Information in NASD does not represent NIOSH policy. Information included in NASD appears by permission of the author and/or copyright holder. More