FWHM Full width at half maximum. Gram GAR Gated Analogue Router. GM Geiger-Muller GZ Ground Zero. Land surface directly beneath or at the site of a nuclear test. SGZ and AGZ occasionally used to distinguish between tests at the surface andin the air. hour, as in R/h. H&N Holmes & Narver, Inc., Orange, CA. and DOE. HEPA High Efficiency Particulate Air (type of filter). Logistics and base support contractor for DNA Mercury. HP Hewlett-Packard. Electronies laboratory equipment. HPGe High Purity Germanium - erystal for detection of gamma rays (also referred to as IG) HQ Headquarters. HV High voltage. IAEA International Atomic Energy Agency. ICRP International Commission on Radiological Protection. IG manufacturer, including desktop computers and Intrinsic Germanium (detector). Also referred to as high purity germanium (HPGe) detector. IMF Instrument Maintenance Facility. IMP Not an acronym, but a trademark owned by the DeLorean Manufacturing Company. Although actually the manufacturer's name for the tracked vehicle used to house the in situ measurement equipment, this term was often used to refer to the entire system. JCS Joint Chiefs of Staff, DOD. JTG Joint Task Group. KAFB Kirtland Air Force Base. keV Kilo electron volt. KT Kilotons (nuclear tests are rated in thousands of tons of TNT). LAB Laboratory. See RADLAB. LASL Los Alamos Scientific Laboratory, Los Alamos, NM. LARC Landing Amphibious Recovery Craft. xix