Document 700wMVdjK6j8q9EZy614gkom8

industrial Hygiene Digest - August, 19U9 962 Radioactivity of Dust. C. Jack (letter to Editor). Mature lb3. 570 [Apr. 9, 19^9). Writing from Prague, the author reportb that vhen dust from air containing 1.5 x 10" curie per cc. of radon was deposited on a glass plate and left there an hour, many tracks of alpha particles of radium C' vere observed. Moet of the radon atoms vere deposited vlth the dust and not directly an the glass, as shorn by experiments vlth dust-free air. It Is reasonable to suppose that artificial radioactive atoms, for example, those atoms left In the air by the explosion of an atomic bomb--vill similarly be adsorbed on dust particles. 963 Radiation Cataracts. Editorial. J7A.MX lTO. "Ella-1219 (Aug. 13, 19^+9). Bince 1905 the entity of radiation cataract has been veil established, both clinically and experimentally. The development of cataracts In young physicists vlth a common history of exposure to cyclotron radiations has relieved Interest In the subject. The injuries are believed due to the lack of knowledge of the hazardous character of neutrons, vblch for certain . organ systems may have four to eight times the effectiveness originally sus pected. Even nov, dosimetric methods for neutrons are unsatisfactory. In the case of roentgen rays, the electrons cause chemical alterations, but the damage to any one cell by one electron Is relatively small, and roentgen rays are relatively effective only against dividing cells. In the case of neutrons, the released ' proton passing through a cell say cause perma nent Injury. Neutrons may Injure the cell at any phase. Ihe urgency for research In this field Is evident. Exposure to Hlcrovaves. W.W. Salisbury, J.W. Clark and H.M. Bines. Electronics 22, 66-67 (May, 19l9). The results of recent experlisente on animals vlth high Intensity 12 cm. radiation Indicate that a dangerous amount of heat may be generated beneath the surface of living tissue vlthout causing fever or pain, The action of radiation on the eye and other tissues le also discussed. BrplosIon-Proof "Speaker". The Signet Development Company, Chicago, has developed a loudspeaker far Intercoms and public address systems, for use In loca tions vhere explosive or combustible gases or dusts may be present. This speaker, said to be both flame-proof and explosion-proof, Is In tended primarily for use In refineries, chemical plants, and munitions manufacturing establishments. The speaker operates Just ar any regu lar loudspeaker except that It Is sold to be Incapable of Igniting dusts or gases surrounding It, should a breakdown In the voice coll or field coll occur.' -- Cham. tag. (July, 19**9)