Cryogenic gases or cryogens refer to gases that have been maintained at a temperature of less than 123K or -150 degrees Celsius. At this temperature they usually turn to liquid. There are three main types of cryogens that include flammable liquids, oxygen and inert gases. Inert liquids are those that are usually unreactive. Examples include neon, nitrogen, krypton, argon and helium. Highly flammable types are the types that burn easily in air.
There are many uses for the cryogens. In the medical field, they are commonly in cryosurgery. Here, they help in treatment of cancer by destroying some of the malignant cells. They are also used in the preservation of both animal and human tissues for future use. Some reactions are associated with production of heat and the cryogens help in the maintenance of a lower temperature.
There are a number of health hazards that are associated with the use of cryogens. When one is exposed to the cryogens or the handling equipment they may suffer tissue injury caused by the very low temperatures. The pattern of injuries is like that of caused by thermal energy and the affected skin takes on a waxy yellow appearance. Mucosal surfaces are at the highest risk.
Asphyxiation is another risk than one should be wary of. Cryogens become heavier as they cool and tend to displace ordinary air. The accumulation of cryogens near the ground reduces the amount of oxygen available for respiration and this is what leads to asphyxiation especially in enclosed spaces. The other mechanism that contributes to this problem is the destruction of lung tissue by the cryogens.
The highly flammable cryogens may explode when they rapidly expand. Gases likely to undergo this include methane, carbon monoxide and hydrogen. A mixture of hydrogen and ordinary air is highly flammable and should be handled with utmost care. Liquid oxygen is equally dangerous and may cause the combustion of materials such as carbon, cast iron and stainless steel.
Due to the many associated risks, one needs to take precautions. Proper thermal insulation prevents ignition. The insulation should be done to the containers and the pipes that are used in the delivery of the cryogens. Special flasks that are non-pressurised are available in the market. They have a loosely fitting cap that allows for the escape of excess pressure but keeps moisture out of the vessel.
Personal protective equipment is strongly recommended. The clothes worn should be kept clean and dry. They should be well fitting and must cover the feet and hands. In the event that the substance penetrates the clothing or gloves, the clothing should be removed immediately. For protection of the face a face mask or goggles can be used.
Cryogenic gases have a wide range of applications. They are, however, very dangerous if not properly handled. Understanding the precautions required is very important. Ensure that you always read the instructions on how to use them. If anything is unclear, make sure that you consult.
There are many uses for the cryogens. In the medical field, they are commonly in cryosurgery. Here, they help in treatment of cancer by destroying some of the malignant cells. They are also used in the preservation of both animal and human tissues for future use. Some reactions are associated with production of heat and the cryogens help in the maintenance of a lower temperature.
There are a number of health hazards that are associated with the use of cryogens. When one is exposed to the cryogens or the handling equipment they may suffer tissue injury caused by the very low temperatures. The pattern of injuries is like that of caused by thermal energy and the affected skin takes on a waxy yellow appearance. Mucosal surfaces are at the highest risk.
Asphyxiation is another risk than one should be wary of. Cryogens become heavier as they cool and tend to displace ordinary air. The accumulation of cryogens near the ground reduces the amount of oxygen available for respiration and this is what leads to asphyxiation especially in enclosed spaces. The other mechanism that contributes to this problem is the destruction of lung tissue by the cryogens.
The highly flammable cryogens may explode when they rapidly expand. Gases likely to undergo this include methane, carbon monoxide and hydrogen. A mixture of hydrogen and ordinary air is highly flammable and should be handled with utmost care. Liquid oxygen is equally dangerous and may cause the combustion of materials such as carbon, cast iron and stainless steel.
Due to the many associated risks, one needs to take precautions. Proper thermal insulation prevents ignition. The insulation should be done to the containers and the pipes that are used in the delivery of the cryogens. Special flasks that are non-pressurised are available in the market. They have a loosely fitting cap that allows for the escape of excess pressure but keeps moisture out of the vessel.
Personal protective equipment is strongly recommended. The clothes worn should be kept clean and dry. They should be well fitting and must cover the feet and hands. In the event that the substance penetrates the clothing or gloves, the clothing should be removed immediately. For protection of the face a face mask or goggles can be used.
Cryogenic gases have a wide range of applications. They are, however, very dangerous if not properly handled. Understanding the precautions required is very important. Ensure that you always read the instructions on how to use them. If anything is unclear, make sure that you consult.
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