Frequently asked questions
General questions
The evaporation of liquid nitrogen, gaseous nitrogen is formed with a low temperature, while its density is greater than that of air. Therefore, the nitrogen after evaporation can accumulate first on the lower level of the room and then gradually create an increased focus around the room. This leads to a decrease in the concentration of oxygen in the air and when its value is below 18%, the person in this room is in serious danger - there is a disorder of the rhythm of the breath, quickens the pulse, and then impaired consciousness, loss of sensitivity, loss of ability to move, nausea and vomiting, disconnected consciousness, and in a few minutes death occurs. A particular danger lies in the fact that it is painless and people are not aware of their condition. In rooms with natural ventilation is allowed to work with open cryogenic receptacles in that case, if the room volume in m3 higher than the volume of the liquid in the Dewar in litres, not less than 7 times.
Short-term contact of skin with liquid nitrogen is not dangerous, since the skin forms a cushion of air with low thermal conductivity, which protects the skin from direct contact with liquid nitrogen. Prolonged contact of liquid nitrogen or material, chilled with liquid nitrogen with the skin or eyes can cause serious damage. Handle liquid nitrogen carefully! In the Strait of liquid nitrogen ventilate the room.
Questions on liquid nitrogen and Dewar vessels
It depends on the type of Dewar and volume, as well as the manufacturer. Dewar vessels the American and European manufacturers have the best performance in terms of evaporation of liquid nitrogen are in the range of from 0.10 to 0.20 l/day for vessels with a volume of 2 to 50 liters. Dewar vessels of most other manufacturers tend to have volatility in the range of from 0.15 to 0.40 l/day. Typically, the data on the amount of evaporation is indicated in the passport or the operating instructions for Dewar. The average time of storage of liquid nitrogen until complete evaporation can vary from several weeks to a year.
It is prohibited to tightly close the neck of the vessel without any abnormal traffic. You should only use regular tubes and caps, which, among other things, prevent the formation of ice in the neck of the Dewar vessel due to condensation of moisture from the atmosphere. With the appearance of mechanical damage and/or "accretion" on the outer surface of the vessel (especially when it is completely freezing!) it is necessary to free the vessel from the liquid nitrogen supply vessel in thawing and contact us for consultation.
Foreign objects in the vessel with liquid nitrogen can create an ice jam and cause the destruction of the vessel.
No.
According to the Rules of the "European agreement concerning the international carriage of dangerous goods (ADR) liquid nitrogen up to 333 kg may be transported without compliance with restrictions for dangerous goods. This rule is confirmed by the Order of Ministry of transport of the Russian Federation dated 08.08.1995 No. 73. May be transported in one transport unit without complying with the above Rules Dewar vessels ck-16, filled with liquid nitrogen, in an amount up to 15 PCs.
Delivery of nitrogen will be made within two working days from the date of the order.
No.
The effect of the overflow device based on the pressure in a cryogenic vessel, when introduced into the liquid warm mass and the effect of gas-lift. The evaporated part of the fluid after sealing of the container neck creating a pressure that forces the liquid through the siphon device is poured into the fill container. Any additional devices for the overflow of liquid is not required.
Part of the overflow device, which is inserted in the Dewar vessel is a rigid structure and adapted only to the vessel a certain height. Use of overflow devices for Dewar flasks with necks of different diameters is possible by the application of an additional sealant.
Dewar vessels YDS-10L или 15L depending on the flow of patients. Cryosurgical apparatus with Criona must be periodically refilled, so you need to choose the vessels that you have overflow device. Pour through the funnel will be uncomfortable and hard.
Questions on Dewar vessels and bioapparatus
In order to avoid increased evaporation of liquid nitrogen is not recommended to place the Dewar in close proximity to heating devices. Store and use liquid nitrogen only in well ventilated areas. Indoors the increased content of nitrogen gas reduces the concentration of oxygen and may cause asphyxia. For more information, see safety Rules when working with cryogenic equipment and liquid nitrogen.
No. Practice has shown that doctors do not like to transfer their cryodestruction of others.
10 nozzles of different sizes and shapes for different purposes.
Can. For this you need to use an additional set of contact probes.
Kristic convenient to remove small tumors - warts, papillomas, moles. A thin metal rod cooled in liquid nitrogen and applied to the affected area.
Dewar vessels YDS-10L или 15L depending on the flow of customers.
Yes, you can.