Thankfully, deserts cool off at night. That relieves the stress on equipment baking under the scorching sun. The reverse is not true in extremely cold regions. Places, such as Siberia, can see the mercury dive below -50°C (-58°F) and not substantially rise for days or even weeks.
Such low temperatures play havoc with delicate hardware, even with the cases used for transportation. Rubber and plastic become brittle in extreme cold and are easily damaged. Seals can fail completely.
Military equipment is designed for use in such conditions. MIL-HDBK-310, “GLOBAL CLIMATIC DATA FOR DEVELOPING MILITARY PRODUCTS”, details the extremes that should be taken into account when designing equipment. This data is incorporated into specifications, such as MIL-STD-810, that define how environmental conditions are to be accounted for during testing.
According to MIL-HDBK-310, the coldest regions outside of Antarctica are Siberia and Greenland. Other high-latitude locations can see similar temperatures. The lowest measured temperature is a bone-chilling -68°C (-90°F), recorded on three separate occasions in Russia. If that sounds fearsome, note that temperatures are measured 1.5 meters above the snow and could be 4° to 5°C (7 to 9°F) lower than at the surface. Further, don’t overlook the added impact of wind lowering the effective temperature.
The challenge in establishing temperature limits for design and test is that the records only cover a relatively short period. To address this, the Department of Defense takes a statistical approach and defines how often certain temperatures might be expected. This frequency-based approach results in temperature “percentages”.
For low temperatures, the 20%, 10%, 5% and 1% temperatures for regions like Siberia and Greenland have been established as – 51°C (-50°F), – 54°C (-65°F), – 57°C (-71°F) and – 61°C, (-78°F). A simpler way to look at this may be to consider that a 10% frequency means that temperature will be seen once every ten years. MIL-HDBK-310 recommends designing for a 20% frequency.
If you’re looking for transit cases that endure extreme conditions, check if they meet military specifications. That tells you they’re built to endure the worst from Mother Nature.
Sierra Cases offers a full line of transit cases that meet military standards. Optional heaters are available to protect your electronics during the worst cold extremes.
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