DCIEM Cache Mystery Cache
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Difficulty:
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Terrain:
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Size: 
(small)
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The cache is not at the posted coordinates, but is nearby. Enjoy the drive, and if you’re a diver, dive safely with a buddy!
DCIEM CACHE
The Canadian Forces Experimental Diving Unit at the Defence and Civil Institute of Environmental Medicine (DCIEM) in Toronto, Canada, developed the DCIEM diving tables and manuals. In 2002, the DCIEM name was changed to Defence R&D Canada - Toronto, but the diving tables and manuals retain the DCIEM name. DRDC Toronto (visit link) is world-renowned for it’s diving expertise.
DCIEM's roots go back to 1939 when the Department of National Defence (DND) recognised the importance of human factors by establishing the inter-departmental Associate Committee on Aviation Medical Research. Sir Frederick Banting, the co-discoverer of insulin, chaired the committee. Another pioneer in human protective systems research was Dr. Wilbur Franks, who developed the Franks Flying Suit, the first anti-G suit used in wartime service.
The post-war years saw many advances in human factors research, and several changes in the Institute's name and organisation. Since 1952, DRDC Toronto has provided its Canadian Forces and industrial clients with an internationally recognised combination of research facilities and expertise.
The results of its research over several decades are consolidated into an algorithm that is used in the DCIEM Manuals and Sport Diving Tables.
Diving Background
When compressed air is breathed at depth, the inert gas, nitrogen, diffuses into the various tissues of the body. Nitrogen diffusion occurs at different rates for the various tissues, depending on tissue density, as long as the partial pressure of the inspired nitrogen is greater than the partial pressure of the gas absorbed into the tissues. The amount of nitrogen that is absorbed increases with the partial pressure of the inspired nitrogen (at depth) and the duration of the exposure.
When the diver ascends, the process is reversed as the nitrogen partial pressure in the tissues exceeds that in the circulatory and respiratory systems. The pressure gradient from the tissues to the blood and the lungs must be carefully controlled to prevent a too rapid diffusion of nitrogen. When the bubble gradient is uncontrolled, bubbles of nitrogen form in the tissues and the blood, which can result in the development of decompression sickness (the Bends).
To avoid decompression sickness divers use various dive tables to plan how deep they can go and how long they can stay at a particular depth. To solve this cache you will have to use the DCIEM standard air decompression table.
WP is N 45° 13.ABC W 075° 48.DEF
To calculate ABC = (the no decompression limit for a diver at 40 ft. x 3) –16
To calculate DEF = (the no decompression limit for a diver at 130 ft.) x 51
Additional Hints
(Decrypt)
Nfx n qvire!