Internal Exposure 1 : Radiation and Radiological Disasters. A path or means by which fire can spread within a building, such as a doorway, an elevator shaft, an open stairway, etc. See: Interior Exposures
Ralph W. Burklin & Robert G. Purington, Fire Terms: A Guide to Their Meaning and Use, National Protection Association, Boston, MA 1980 USA. (Guide: Meaning and Use, Nat Prot Association Fr Srvc - Amer) {457}