Safety First This Breeding Season Safe practices for transportation and storage of semen tanks By B. Lynn Gordon for the Red Angus Magazine What could be as crucial as your sire selection decisions this breeding season? The simple answer: focusing on mind-over-matter when handling and storing semen tanks. During the breeding season, the transportation of cryogenic containers/tanks (commonly referred to in the beef industry as “semen tanks”) or accessing straws from tanks in storage at your ranch can be a daily practice. Using mindover-matter, you can keep yourself and others safe this breeding season. Nitrogen – A Silent Killer Liquid nitrogen (LN2) is nitrogen in a liquid state. When nitrogen is converted to a liquid form, it becomes a liquefied gas which must be kept at extremely low temperatures. Liquid nitrogen will expand to produce 700 times the volume of gas when vaporized. This rapid and extreme expansion can lead to oxygen displacement. The oxygen level in fresh, outside air is 20.9%. Research conducted by the National Institute for Occupational Safety and Health describes 19.5% oxygen as the onset of an oxygen-deficient environment. At oxygen levels lower than 19.5%, people immediately begin to feel the effects. The lower
Health Effects at Each Level of Percent Oxygen % Oxygen Physiological Effects 20.94%
Normal
19.5%
Unnoticeable physiological effects
19.0%
Unnoticeable physiological effects
18.5%
Fatigue
18.0%
Fatigue
16.0%
Impaired
14.7%
IDHL (Immediately Dangerous to Health or Life)
Source: National Institute of Occupational Health and Safety and ABS Global
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RED ANGUS Magazine n April 2021
the percent of oxygen in the air, the more tragic the outcome. Nitrogen has no warning properties. It is odorless, colorless, tasteless and non-irritating, reports the Office of Research, Environmental Safety and Health Department at Utah State University. Humans cannot detect nitrogen’s presence, thus increasing the risk as an asphyxiant when nitrogen displaces oxygen in the air to levels below that required to support life. Exposure to nitrogen can cause dizziness, nausea, sleepiness, vomiting, loss of consciousness and even death. Death may result from errors in judgment, confusion or loss of consciousness that prevents self-rescue. At low oxygen concentration, unconsciousness and death may occur in minutes and without warning. Industry Study Results ABS Global, DeForest, Wisconsin, conducted several studies in 2010 to learn about the hazards of transporting and storing liquid nitrogen semen tanks. Their findings include: Transportation Precautions: ABS placed two newly filled tanks in the back seat of a crew cab truck. In three minutes, the cab of the pickup was unsafe for human occupancy. One hour later, the level of oxygen had depleted to 14.7%. In a similar test, one of the tanks was tipped on its side, and in less than one minute, the oxygen in the cab had fallen below 18.3%. Ten minutes later, the oxygen level had depleted to 9.7%. “Proper transportation of semen tanks is needed for people to remain safe,” said Ron Zeihen, a safety specialist at ABS. Zeihen explained there is continual venting of nitrogen from the tank to prevent an explosion. In an air-tight vehicle, this release of
Proper Transportation – Semen tanks should only be transported securely in the bed of a truck or in a sealed compartment where no passengers are present or may enter. (Photo by ABS Global) nitrogen can be deadly. “There are too many risks involved with hauling a semen tank inside the passenger compartment of a vehicle rather than in the bed of the pickup truck.” Undetected leaks, the tank’s age and the length of time in an enclosed space all affect the risks of hauling a tank inside the passenger compartment of a vehicle. Storage Precautions: ABS also conducted studies at its cryogenic storage warehouse where 10 newly filled tanks were placed into a 12’ x 15’ (1,440 cubic feet) enclosed, non-ventilated room. The result: it took 18 minutes for the air to become unsafe for human occupancy. The longer the tanks sat, the more the oxygen level continued to decrease. To keep the tank safe, out of the way and out of extreme weather, producers might place the tank in a confined room or closet. “If you have tanks stored in a room or closet, make sure it is always ventilated. A passthrough air vent in the door can help keep airflow in the room,” Zeiben said. Safety First Shocked to hear the results of the ABS
