00000nam 2200000zi 4500 9.952178 CaOODSP 20250819155237 m o d f cr |n||||||||| 250610e197707##onca ob f|0| 0 eng d CaOODSP eng rda CaOODSP n-cn--- D68-25/9-1977E-PDF Crabtree, R. B., author. Exposure to ultrasonic cleaner noise in the Canadian Forces / R.B. Crabtree, S.E. Forshaw. Downsview, Ontario : Behavioural Division, Defence Civil Institute of Environmental Medicine, Department of National Defence - Canada, July, 1977. 1 online resource (v, 28 pages) : illustrations text txt rdacontent computer c rdamedia online resource cr rdacarrier DCIEM technical report ; No. 77X45 Digitized edition from print [produced by Defence Research and Development Canada]. Includes bibliographical references (page 7). "The high-frequency noise produced by ultrasonic cleaning devices at CFB North Bay and CFB Trenton is sufficiently intense to produce effects such as nausea, headaches, tinnitus and fatigue among exposed personnel. Although the 20-kHz one-third octaveband sound pressure levels observed close to these units are well under 140 dB (the level below which damage to the human ear is thought not to occur), they nevertheless exceed the levels recommended for hearing conservation (105 dB at an operator's position, 95 dB within 15 feet of an operator). The most effective means of reducing the noise radiated from these cleaners is to contain each unit in an appropriately ventilated enclosure or room. Personnel operating or working close to units not enclosed should wear hearing protection"--Abstract, page v. Ultrasonic cleaning. Ultrasonic waves Physiological effect. Nettoyage par ultrasons. Ultrasons Effets physiologiques. Defence and Civil Institute of Environmental Medicine (Canada), issuing body. Canada. Department of National Defence, issuing body. DCIEM technical report ; No. 77X45. (CaOODSP)9.943618 PDF 1.18 MB https://publications.gc.ca/collections/collection_2025/rddc-drdc/D68-25-9-1977-eng.pdf