Protection From Power Failure

Power failures and electrical outages can happen undetected at any time of the year. Losing 20 years of investment in specimen gathering is not a pleasant prospect! Fortunately, the impact of a power failure can be minimized.

If you have some say in directing the facility's infrastructure, you'll want to be prepared with an action plan that gives you the best protection available. As usual, the best protection costs the most. But there are some low-cost alternatives that are sensible fixes.

1.0 Alternate Automatic Backup Systems

The two following options are the best of all solutions to apply. They are, however, likely to be expensively fitted into your plan and require that your facilities people be involved.

1.1 Back-up/Emergency Power Circuit

Your facility may have an on-site fuel powered electric generator that "kicks in" when the hydro power fails. An emergency power circuit may be available that provides adequate power for at least one of your ultra-low temperature freezers in the event of a electrical utility interruption.

Make sure that the most precious long term storage specimens are placed in a freezer unit powered on that circuit. If electrical current from this emergency circuit is limited, choose a freezer that draws the least current. If the main electrical power fails, emergency power will give some security for your specimen investment.

Naturally, it makes no sense to have all lab equipment on emergency back-up power unless your facility has the luxury of unlimited operational funds. Any process equipment (centrifuges, incubators, analyzers, etc.) should be left on normal power.

1.2 Liquid Gas Back-up

A back-up addition, or alternative, to emergency power circuit is liquid CO2 or liquid nitrogen (LN2) back-up systems. If the freezer is equipped with such a system, make sure that liquid gas supply tanks are topped up. This topping up process should be administered with a written responsibility and action log.

2.0 Non-Automatic Preventive Measures

If you are unable to incorporate either of the automatic systems described above, you're not dead if the power fails! And, even if you do have the automatic systems the following steps should be part of an over all failsafe plan.

2.1 Dry Ice

An alternative to automatic liquid injection is to secure a source of dry ice from a reliable standby supplier when the failure does occur. A notice of whom to call for this supply should be posted on or near the important freezer. One can then manually place the dry ice blocks in the freezer chamber as needed in order to maintain frozen temperatures.

2.2 Fill the Chamber

Ultra low temperature freezer chambers are well insulated. Temperature warm-up will take longer (in the event of power interruption) if there is a full chamber i.e. large thermal mass. Use pre-frozen thermal packs, pre-frozen water containers, or other frozen material to fill the chamber. Warning: do not attempt to freeze large quantities of water in the chamber at the same time.

2.3 Lower the Temperature

Set the freezer to run at its lowest temperature setting. Temperature warm-up will be prolonged just that little bit more. Properly calibrated, the freezer should easily be capable of running at the lowest temperature setting while still cycling on and off.

Also, take steps to verify that the temperature displayed on the unit is actually what's inside the chamber.

2.4 Instruct all Staff

Whether or not the temperature and power is monitored remotely, make sure to advise all staff that freezer doors should not be opened in the event of a temperature alarm indicated on the unit. The contents will remain frozen for up to three days if no warm air is allowed to enter the chamber. The only acceptable purpose for opening the door is to add dry ice.

2.5 Invest in Preventive Maintenance

Last, but not least, when was the last time the freezer was inspected and serviced? Is the unit operating properly? Caltech customers currently on CCM Preventive Maintenance Programs already know the security of this service.

For those who wish to have an on-site evaluation or who have further questions, please contact us.