Patty's Industrial Hygiene, Physical and Biological Agents. Группа авторов

Чтение книги онлайн.

СКАЧАТЬ 257 95.1 0.01051 281 87.0 0.01149 234 104.5 0.00957 258 94.8 0.01055 282 86.7 0.01153 235 104.0 0.00961 259 94.4 0.01059 283 86.4 0.01157 236 103.6 0.00965 260 94.0 0.01063 284 86.1 0.01162 237 103.2 0.00969 261 93.7 0.01067 285 85.8 0.01166 238 102.7 0.00973 262 93.3 0.01072 286 85.5 0.01170 239 102.3 0.00978 263 93.0 0.01076 287 85.2 0.01174 240 101.9 0.00982 264 92.6 0.01080 288 84.9 0.01178 241 101.5 0.00986 265 92.3 0.01084 289 84.6 0.01182 242 101.0 0.00990 266 91.9 0.01088 290 84.3 0.01186 243 100.6 0.00994 267 91.6 0.01092 291 84.0 0.01190 244 100.2 0.00998 268 91.2 0.01096 292 83.7 0.01194 245 99.8 0.01002 269 90.9 0.01100 293 83.4 0.01198 246 99.4 0.01006 270 90.6 0.01104 294 83.2 0.01202 247 99.0 0.01010 271 90.2 0.01108 295 82.9 0.01207 248 98.6 0.01014 272 89.9 0.01112 296 82.6 0.01211 249 98.2 0.01018 273 89.6 0.01117 297 82.3 0.01215 250 97.8 0.01022 274 89.2 0.01121 298 82.0 0.01219 251 97.4 0.01027 275 88.9 0.01125 299 81.8 0.01223 252 97.0 0.01031 276 88.6 0.01129 300 81.5 0.01227

      ^a A. C. Fieldner, S. H. Katz, and S. P. Kinney, “Gas Masks for Gases Met in Fighting Fires,” U.S.

      Bureau of Mines, Technical Paper No. 248, 1921.

Part V Physical Agents

IONIZING RADIATION

Herman Cember Ph.D. PE CHP^†, and Thomas E. Johnson Ph.D. CHP

INTRODUCTION

      Ionizing radiation may be defined as electromagnetic (X‐rays and gamma rays) and particulate radiation (alpha and beta particles, electrons, neutrons, and protons) with sufficient energy to disrupt an atom or a molecule. This is done by knocking out an electron, thereby “ionizing” the atom or molecule.

      Knowledge of radiation and safety problems associated with its use goes back more than 100 years, with the discovery of X‐rays in 1895 by Wilhelm Roentgen. On the same day that Roentgen announced his discovery, Emile Grubbe, a physicist working in Chicago with an apparatus similar to Roentgen's, developed severe skin burns after handling an energized cathode ray tube similar to the one used by Roentgen. This was the first work‐related injury from radiation. In 1896, Antoine Henri Becquerel discovered radioactivity while working with an ore called СКАЧАТЬ