When I worked at the W. M. Keck Observatory on the 13,796 feet very high altitude summit of Mauna Kea, we would routinely be engulfed in cold clouds of helium and nitrogen gas as we discharged it into the video camera systems daily. The management team never warned us that we were in a hazardous oxygen deprived environment during this activity that was known for its ability to adversely affect physical and mental health, and possibly bring on death by asphyxiation.

The golden rules of eating from the unlimited food buffet: 1. Eat the hot food, as it is the least likely to food poison you. 2. Avoid the cold food, as it may have bacterial contamination. 3. Wash your hands after eating, as they may have bacterial contamination from the handles of the food ladles.

Snow cleaning of the world's largest telescope mirrors was an impressive sight. The optics technicians would climb into a huge telescopic boom lift and spray immense clouds of cold carbon dioxide snow and gas onto the ten meter diameter mirrors high above the floor indoors. It would cause some of the accumulated dirt to magically fall off, leaving it less dirty.

The very high altitude summit of Mauna Kea was always cold and the telescope domes were chilled to the nighttime temperature which was often below freezing in wintertime.