Scientist Wearing PPE opening a Cryo TankCryogenic tanks, or cryotanks, are storage systems used to store frozen biological materials and offer a number of unique benefits. At XiltriX, we offer lab monitoring services to help ensure cryotanks and supporting systems are running at maximum efficiency and with complete safety.

How to Reduce Risks Associated with Cryogenic Storages

Cryogenic tanks, or cryotanks, have myriad uses, and even more perceived uses.

Ask the layperson, and they’ll say something along the lines of, “Cryotanks… those are the things where you can freeze your head or body until the next century, right?” And… well… yes, right. And they can also be used to store rocket fuel and a wide range of other materials.

However, for most modern clinical labs, cryotanks are storage systems used to store frozen biological materials that need to be kept at literally unearthly cold temperatures.

Cryotanks are incredibly sophisticated storage vessels. The basic structure of a cryotank consists of two shells, an inner shell and an outer shell. The inner shell (usually made of stainless steel) is the product/materials container and the outer shell (usually made from carbon steel) is the vacuum jacket. Air is removed from the space between the two shells to create a vacuum, which helps provide extraordinary thermal insulation.

Even with this seemingly simple construction, there’s much that can go wrong, and when it does, the costs can be astronomical and the materials damaged irreplaceable.

We’re going to explore a few means of mitigating risk in and around cryotank usage for the modern lab, and help ensure best practices are in place across the board and within the tanks.

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Cryotank Use, Cross-industry

Like NASA needs rocket fuel, many companies across many industries require cryogenically stored gases for a wide range of industrial applications (perhaps their most common use). But in life sciences and clinical labs, cryogenic tanks are often used for the storage of samples such as embryos and oocytes for fertility clinics.

For some industries, cryotanks serve as a cost-saving replacement to bulkier, and less-effective, means of storage, such as fuel transport. For those use cases, one cryotank can replace hundreds of storage cylinders.

Naturally, not all materials — biological or otherwise — require the robustness of a cryotank for storage, and the tanks are typically used when materials must be stored over longer periods of time (i.e., when materials need to be put into a literal “deep freeze”).


Risks in and Around Cryotank Storage

As with most heavy-duty lab equipment, there are more than a few risks involved in using cryotanks, and ensuring you’re monitoring each individual tank is critical.

In general, severe frostbite or cryogenic burns are possible if cryogenic liquids come into contact with the skin. A rarity, but it can happen. Also, cryogenic liquids can cause major damage if they come into contact with other equipment or the infrastructure of a laboratory, such as pipes, laboratory benches, and laboratory floors.

More common is the risk of asphyxiation, if liquid nitrogen is used or released in a poorly ventilated area. Liquid nitrogen can rapidly evolve into nitrogen gas, and the gas can then displace the oxygen in a room, leading to asphyxiation.

Finally (though a rarity in the lab world), cryogenic storage can pose an explosion risk due to rapid pressure changes that can occur within cryogenically stored liquefied gas.

Cryogenic tanks are usually fitted with pressure release valves (which can and should be monitored), so if pressure does begin to build up inside them, it can be released gradually and safely in a controlled manner.


Cryotank Explosion: The Risk Realized in a Texas Lab

Cryotanks exploding is not theoretical. A widely circulated accident report following an explosion involving one of these tanks highlighted a number of serious errors that any lab should be on the lookout for.

First, the tank in question was old — these tanks have a shelf life, and once they reach a certain age they need to be replaced. The pressure release valves on the tank in question had failed in the past, and instead of being replaced with new valves, the tank was simply sealed with metal plates.

One January morning, 3:00 am, with no one on-site to monitor, the pressure in the tank started spiking. With no properly functioning pressure release valves, pressure built up  — naturally — until the tank exploded and shot upwards like a rocket.

It passed through the floors above it, finally coming to rest on the third floor of the building. The explosion stripped tiles off the laboratory floor. The tank smashed into water mains and electrical cables, cracking concrete ceilings, and more. The damage was massive.

The bright side was the timing. If this incident had taken place during the day, more than just pipes and ceilings would have been damaged. Better, if these tanks had been properly monitored and risk-assessed, this incident could have been entirely avoided.


Protective Measures for Cryotank Safety

Explosions. Leaks. Asphyxiation. While these sound like major, major risks, the good news is that you can most always entirely avoid these lab disasters simply by being proactive. Here are a few things clinical lab managers can do to protect their facility, equipment, and people.

First, training. Ensure that all personnel who use and come in contact with cryogenic tanks and liquids, perform processes that involve the use of cryogenic tanks, or interact with any samples stored in them, have been trained in the specifics of handling the tanks and ancillary equipment.

Safety precautions should be taken at all times, and appropriate protective gear should be worn, such as goggles, helmets, gloves, and overalls.

Next, maintenance. All equipment — such as the tanks themselves, their safety valves and connectors, and any pipework or instruments used for cryogenic processes —  must be maintained to the highest standard, and replaced regularly according to a planned maintenance schedule (typically available through the tank provider). If any signs of damage or wear and tear are noticed, damaged components must be replaced immediately.

More specific to biotech and IVF businesses, where eggs and embryos are often stored using liquid nitrogen, systems must be implemented to protect against nitrogen levels dropping too low in the cryotanks, endangering the samples stored therein. Daily tank inspections, alarm systems that send alerts when levels are low, or systems that automatically replenish the cryotanks to appropriate levels are a few tactics often employed.

In the end, mitigating risk in cryotank storage systems comes down to awareness, and that means 24/7/365 monitoring of cryotank functionality and temperatures. Material temperature fluctuations can quickly, even immediately, result in damage at a chromosomal level, tissue sample destruction, cell cultures developing ice crystals… and knowing about any temperature change as soon as it happens can help create far better outcomes.


How XiltriX Helps Mitigate Cryotank Storage Risks

A state-of-the-art laboratory monitoring service is critical. Through real-time monitoring of temperatures and pressures inside cryotanks and other storage tanks, XiltriX provides both peace of mind and leads to a plan of action.

If the temperature in a cryotank begins to increase, XiltriX can immediately alert appropriate staff. XiltriX leverages real-time data from temperature outputs, and other parameters relating to cryogenic storage systems, to:

  • produce automated reports to help your laboratory adhere to regulatory requirements;
  • receive immediate alerts to potentially dangerous changes in LN2 level, pressure, or ambient O2 concentrations;
  • improve quality control and assurance; and
  • simplify the audit process.

Cryotanks are becoming more and more critical in the modern lab. Learn more about them, and other cold storage solutions, in our eBook, Lab Equipment Monitoring - the Ultimate Guide:

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