The Z Pulsed Power Facility, informally known as the Z machine, is the largest X-ray generator in the world and is designed to test materials in conditions of extreme temperature and pressure. Operated by Sandia National Laboratories, it gathers data to aid in computer modeling of nuclear weapons and eventual nuclear fusion pulsed power plants. The Z machine is located at Sandia's main site in Albuquerque, New Mexico.

The interval between two depths in a well containing a reservoir or other distinctive characteristics.
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Specific areas where restrictions apply e.g. safety zone, hazardous zone (around an offshore installation), danger room (military activity area), etc.