The potential hazards from these sources depend on whether they are used as stationary or portable units. ... Portable units are often transported to construction sites to check welds on metal structures and pipes; they can be very small and ... of soils and asphalt usually contain two radioactive sources: cesium 137 (the gamma source) and a mixture of americium 241 and beryllium (the neutron source).
|Title||:||Disease and the Environment|
|Author||:||Borden Institute Walter Reed Army Medica, David P. Deeter|
|Publisher||:||Government Printing Office - 2000-04-01|