The permanent storage -80°C chambers are situated within a -20°C walk in chamber. Manufactured by Bahnson Environmental Systems, this set up allows for greater storage space at a much lower energy expenditure than traditional upright and chest freezers commonly used for sample storage.
General/temperature monitoring:
There are extensive safety measures in place to ensure that no loss of temperature will affect the samples stored within the Freezer Farm. The measures in place are designed to account for equipment failure, power outages, and natural disasters. The temperature of the -20°C walk-in environment and each of the -80°C chambers are monitored on an Alerton system which will alert in the event of a loss in temperature or door being left open for an excessive amount of time. In the event of an alarm, there are a number of individuals who will be contacted to assess the situation and ensure all samples are safe while the issue is being resolved. The Point-of-use -80°C Freezers are monitored on a Rees system which will operate similarly, alerting if the temperature begins to increase or there is a loss of power to the unit.
Backup power and Temperature control:
The -80°C chambers are powered from one of two -80°C compressors. These compressors operate on a lead-lag system. Each compressor runs for twenty-four hours before switching over to the other one, this keeps the compressors exercised which will prolong the life of the equipment and ensure that both are in working order in the event that one compressor becomes unusable. In the event one of the compressors malfunctions, the other will take over and operate continuously until the damaged compressor can be repaired. In the event of a power outage, the Freezer Farm is hooked up to the hospital’s emergency generator with the highest level of priority. In the extremely unlikely event that both the hospital power and generator are non-functional, there is a back-up liquid nitrogen infusion system which can keep the -80°C chambers at temperature for about six hours per tank. In the event that the liquid nitrogen will be needed for an extended period of time, there is a system in place where a micro bulk truck with liquid nitrogen can be parked in the loading dock and hooked up to our Liquid Nitrogen infusion system to cool the Freezer Farm. In addition, due to the way the chambers are situated within the -20°C walk-in environment, as long as the doors are not opened the chambers will remain at temperature for 8 hours without power.
Access Control:
In addition to the safety measures against temperature fluctuations, the Freezer Farm is also strictly access controlled. A limited amount of people have access to the area and the door are monitored by video to record anyone who enters the -20°C walk-in environment to access the -80°C chambers. We know that the samples being stored within the Freezer Farm are extremely valuable and irreplaceable so we have taken extensive measures in protecting them. Only Freezer Farm staff will be permitted to access the chambers. Any requests for the return of samples MUST go through the Freezer Farm manager who will locate the samples and place them in the Point Of Use freezers in the main lab for pick-up. Investigators will not be permitted to take their samples directly from the -80°C chambers. This is to ensure that no other samples are inadvertently misplaced. All samples in the Freezer Farm are barcoded and their location will be logged in the Freezerworks database.