Mr. GREG BOWER (International Association of Bomb Technicians and Investigators): For nitroglycerin to be transportable, it has to be kept very cold, not freezing, but very col.

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The weather was perfect, not very hot like last year, but not too cold either.

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You should also be aware that almost none of us have air conditioning: our peak energy demand is very definitely in these cold winter snaps, not in summer for cooling.

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They were wearing wetsuits and, over their wetsuits, foul-weather gear, but, even so, they were cold, and in the event that they became fully submerged they would not have survived for very long.

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