Shipping Regulations for Nitrogen Cylinders
Nitrogen cylinders are highly compressed containers of nitrogen gas. The shipment of nitrogen cylinders requires strict adherence to federal shipping regulations. It must follow the regulations or the Department of Transport (DOT). The labeling and identification required on the shipping containers is also stipulated by the title 49 of the DOT regulations. Before stating the shipping regulations of nitrogen, it is important to understand the physical properties of nitrogen, as they determine the shipping stipulations on nitrogen.
Physical Properties of Nitrogen
Nitrogen is an inert, colorless, odorless, and tasteless gas that does not support combustion. Nitrogen also does not support respiration, hence an exposure to a pure nitrogen atmosphere can cause death without any warning. Nitrogen is slightly lighter than air and is only slightly soluble in water. It is for this reason that strict safety measures are followed for the shipping of nitrogen. Nitrogen is naturally present in the atmosphere at a concentration of 78.1 percent.
Adverse Health Effects of Nitrogen
A direct contact with directly expanding nitrogen can cause frostbite, redness of skin, blistering, and a change of skin color to gray or white. Gaseous nitrogen causes asphyxiation by oxygen deficiency. Nitrogen should be shipped very carefully, and care should be taken to look for symptoms of asphyxiation. Symptoms of nitrogen asphyxiation include rapid breathing, muscular coordination problems, emotional instability, and fatigue. Proper care should be taken during shipment as nitrogen asphyxiation can cause death within seconds.
Nitrogen transportation cylinders are manufactured according to DOT regulations that stipulate every shipping detail, including the material of the cylinder, the method of cylinder manufacture, testing, etc. Gaseous nitrogen is shipped in high-pressure cylinders rated at 2,200 psig. The weight of the cylinder is an important consideration; if a leakage occurs, the weight of the cylinder will prevent the cylinder from turning into a rocket. The weight of the cylinder depends on the grade of steel used in the manufacture of the cylinder; the common weight of a 2,200 psig cylinder is 150 lbs.
Safety of Cylinders during Shipping
Cylinders are provided with safety valves and a steel cap to protect them from any damage. Nitrogen cylinders are also equipped with pressure relief devices to protect over-pressurization. The pressure-release devices must be used cautiously since contact with nitrogen can be fatal. For a shipment of nitrogen, the stampings on a cylinder are equally important. Cylinder stampings must have the symbol of DOT. The stamping should also consist of other cylinder details like date of manufacture and cylinder serial number.
Nitrogen is a DOT hazard class 2.2 material. The shipments must comply with DOT regulations. Air shipments should comply with IATA (International Air Transport Association) and ICAO (International Civil Air Organization) dangerous goods regulations. The marine shipment of nitrogen should comply with International Maritime Organization (IMO) regulations. The packages of nitrogen transport should have either “UN/DOT specification” or “UN/DOT authorized” stamps on them.