Vibration - 974 entries found

Your search criteria are

• Vibration

1974

CIS 75-73 Koss L.L., Alfredson R.J.
Identification of transient sound sources on a punch press.
The sources of transient noise on a 4-t punch press were located through the use of statistical correlation techniques (multiple-input correlation theory). It was found that sound was radiated due to changes in the force time curve resulting from material fracture, material cutting and by the take-up of clearances between shafts and bearings. If the frequency content of the region of change in the force time curve is near resonance frequencies of the structural elements of the press, resonances will be excited and noise will be radiated. Ringing vibrations of structural elements could be prevented by isolating the C-frame from its supporting structure.
Journal of Sound and Vibration, 8 May 1974, Vol.34, No.1, p.11-33. Illus. 14 ref.

CIS 75-72 Reynolds D.D.
Vibration characteristics of non-isolated chain saws.
In order to reduce the excessive and harmful vibration amplitudes encountered in hand-held power tools, it is necessary to understand the vibration mechanisms of the tool. A study was made of the acceleration power spectra and structural resonance conditions in a non-insulated medium-sized chain saw, weighing around 5.5kg. The test procedures are described. With the saw operating at normal speed, vibration was due primarily to the shaking forces caused by the unbalanced reciprocating masses of the slider-crank mechanism and the rotating unbalance of the saw clutch and flywheel. The vibration response at frequencies corresponding to the harmonics of the shaking forces was amplified because these frequencies coincided with the structural resonant frequencies of the saw. The test results indicated that the interaction of the cutting-chain and the wood during cutting operations contributed little to the overall vibration response of the saw.
Journal of Sound and Vibration, 8 Feb. 1974, Vol.32, No.3, p.371-382. Illus. 6 ref.

CIS 75-71 Jones D.I.G.
Temperature-frequency dependence of dynamic properties of damping materials.
The behaviour of damping materials under strain is considered and some of the simpler and more reliable techniques for measuring the complex modulus properties of elastomeric and other materials, as functions of frequency, temperature and strain, are reviewed (resonance tests, vibrating beam tests, etc.). The results of tests carried out on various materials (filled silicone elastomer, acrylic adhesive, silicone potting compound, filled nitrile rubber, polymer blend, vitreous enamel) are reproduced, and the data obtained are reduced to a standardised form useful for engineering purposes.
Journal of Sound and Vibration, 22 Apr. 1974, Vol.33, No.4, p.451-470. Illus. 22 ref.

CIS 74-1889 Malyšev Ė.N., Skorodumov G.E.
Concerning the effects of infrasound on the human body
K voprosu o vlijanii infrazvuka na organizm [in Russian]
The higher levels of acoustic pressure found in the sound frequency spectrum of certain machinery (turbines, compressors, fans, diesel engines) are situated within the infrasound frequency band. Their intensity exceeds 100dB and may in some cases reach 135dB. The article describes an experimental chamber where biological research on exposure to infrasound was carried out, demonstrating that low-frequency sound causes the human internal organs to vibrate. These vibrations give rise to discomfort, headache, inappetence, nausea and fatigue. Infrasound control is based on the same principles as noise control and ultrasound control.
Gigiena i sanitarija, Mar. 1974, No.3, p.27-30. Illus. 1 ref.

CIS 74-1877 Laitinen J., Puranen J., Vuorinen P.
Vibration syndrome in lumbermen working with chain saws.
An investigation was carried out in Finland to determine the incidence and type of upper extremity symptoms and the radiographic changes in the carpal bones of lumbermen working with chain saws under cold conditions. 81% of the subjects investigated had upper limb symptoms including numbness, muscular weakness, white hands and tremor related to length of work. The make of saw, the use of a warm handle or vibration absorber and smoking habits did not seem to modify the symptoms. 38% of the workers had some radiological changes in the hands and wrists, and 26% has small cystic transparencies of the carpal bones.
Journal of Occupational Medicine, Aug. 1974, Vol.16, No.8, p.552-556. Illus. 10 ref.

CIS 74-1583 Schoenberger R.W.
An investigation of human information processing during whole-body vibration.
Experiments were conducted using vertical vibration of seated subjects to differentiate mechanical interference effects on peripheral processes from generalised stress effects on central processes. The results indicate that performance of the type represented by the "memory-reaction time" task used is susceptible to mechanical interference with peripheral processes, but is essentially immune to any central processing effects from the general stress of the vibration.
Aerospace Medicine, Feb. 1974, Vol.45, No.2, p.143-153. Illus. 42 ref.

CIS 74-1580 Roure L., Tisserand M.
Vibrations from construction equipment - Protection afforded by conventional seats. Presentation of a seat designed by the INRS
Vibrations des engins de chantier - Protection offerte par les sièges conventionnels. Présentation d'un siège conçu par l'INRS. [in French]
Drivers of construction equipment are exposed to low-frequency vibration whose duration occasionally exceeds permissible limits. An account is given of experimental studies carried out by the INRS (French National Research and Safety Institute) on conventional seats; their performance is compared with that of a new air-hydraulic seat made from series components used in automobile construction, which gave excellent results.
Cahiers de notes documentaires - Sécurité et hygiène du travail, 1st quarter 1974, No.74, Note No.877-74-74, p.15-37. Illus. 10 ref.

CIS 74-1274 Hansson J.E., Wikström B.O.
Vibration stress on drivers of forestry machines
Vibrationsbelastning på skogsmaskinförare [in Swedish]
Report of an investigation into the vibration to which drivers of modern off-the-road skidding tractors and logging machines are exposed via the seat. Vibrations was studied in vertical, lateral and forward-backward directions. The accelerometer signals recorded by telemetry were analysed in 1/3 octave bands. The vibration frequency was found to be mainly in the 0.25-4Hz range for both groups of machines. Acceleration levels varied greatly according to the type of machine. Comparison with a proposed ISO standard for evaluation of human exposure to whole body vibration (ISO/DIS 2631) disclosed that the vibration of most machines was within the range of 1.5-5h of permissible exposure per day. The permissible limits recommended by the standard were exceeded on 2 of the logging machines. Horizontal vibrations had a critical effect on the duration of permissible exposure.
Institutionen för skogsteknik, Rapporter och uppsatser, Nr.67, 1974. Skogshögskolan, 770 73 Garpenberg, Sweden. 28p. Illus. 12 ref. Price: Swe-cr.25.00.

CIS 74-1273 Petrusewicz S.A., Longmore D.K.
Noise and vibration control for industrialists.
This book is aimed primarily at people working in industry who have little or no knowledge of noise and vibration control but who may be called upon to keep noise and vibration levels within acceptable limits. Chapters are devoted to fundamentals of noise and vibration, principles of noise and vibration control (absorbing materials, vibration isolation) and the techniques available for noise and vibration measurement. British and international standards are reviewed, and a chapter is devoted to hearing conservation. The book also presents a case study of the various noise aspects of the design of a new foundry building.
Paul Elek (Scientific Books) Ltd., 54-58 Caledonian Road, London N1 9RN, United Kingdom, 1974. 284p. Illus. Price: £6.50.

CIS 74-1267 Lidström I.M.
The effect of local vibration on the upper extremities
Lokala vibrationers inverkan på övre extremiteterna [in Swedish]
Comprehensive survey on the effects of local vibration during both temporary and long-term exposure: disorders observed; occurrence of injuries; aetiology and pathogenesis; diagnosis; progress of injury and methods of treatment. The study is based on medical and laboratory work and on field investigations. Details are given of all equipment used. A method for recording the vibration energy absorbed (handle equipped with strain gauges and accelerometers) was developed in co-operation with the Swedish Aeronautical Research Institute. The author concludes that the energy absorbed per unit time seems to be an important factor in the causation of vibration injury.
Arbete och hälsa - vetenskaplig skriftserie, 1974:8. Arbetarskyddsstyrelsen, Fack, 100 26 Stockholm 34, Sweden, 1974. 128p. Illus. 169 ref. Price: Swe-cr.26.00.

CIS 74-1258 Blair H.M., Headington J.T., Lynch P.J.
Occupational trauma, Raynaud phenomenon and sclerodactylia.
The development of cutaneous sclerosis in persons with occupational Raynaud's phenomenon is believed to be unusual, but the findings in 2 cases described support the view that while occupational factors alone are probably insufficient to cause sclerodactylia, vibration together with cold exposure and positional factors may precipitate cutaneous sclerosis in those genetically or otherwise predisposed to the development of the condition.
Archives of Environmental Health, Feb. 1974, Vol.28, No.2, p.80-81. 10 ref.

1973

CIS 76-392 Guide to the safety aspects of human vibration experiments.
Much of the available information on the effects of vibration on man is provisional or even contradictory. This publication applies primarily to laboratory vibration facilities, to provide guidance to those engaged in experimental work. It is not a binding code of safe practice. It comprises 4 main sections: general considerations (inherent and extraneous risks, subject's consent, ethical and legal aspects); specification, design and choice of vibration-generation equipment (especially safety measures); selection of subjects; experimental procedures. Appendices: application form; limits of acceptable vibration and shock ("fatigue-decreased proficiency boundary", "exposure limit", "reduced comfort boundary"); medical contraindications; description of typical electro-hydraulic vibrator system.
DD 23:1973, British Standards Institution, 2 Park Street, London W1A 2BS, United Kingdom, June 1973. 23p. Illus. Price: £2.00.

CIS 75-512 Noise, vibration and exhaust gases in forestry work
Bruits, vibrations et gaz brûlés dans l'industrie forestière. [in French]
French translation of: Lärm, Vibration, Abgase bei der Waldarbeit. Die Waldarbeit, Solothurn, Switzerland, 1971, Vol.23, No.3, p.3-18. Illus. Subjects dealt with in this issue include: hearing damage caused by noise in forestry work; disorders due to use of chain saws; measurement of chain saw exhaust gases; 1971 technical report on noise and vibration measurement; noise, vibration and exhaust-gas control measures.
Traduction INRS 14 B-73, Institut national de recherche et de sécurité, 30 rue Olivier-Noyer, 75680 Paris Cedex 14, France, 1973. 21p. Illus.

CIS 74-1887 Starikov G.A., Grjaznov V.I., Mikulinskij A.M., Koldunov V.N., Tihonov N.T., Zaharov Ju.A.
Vibration damping and silencing of a pneumatic grinder
Vibro- i šumobezopasnaja pnevmatičeskaja mašina [in Russian]
Description of a portable straight pneumatic grinder with a tubular main grip (consisting of a constant-pressure air tube) and an air-cushioned rotating sleeve-grip which serves as a control. The air tube grip has been patented in the USSR. Use of these vibration-damping handles enables the level of the vibrations transmitted to the operator's hand to be kept below the threshold limit; it also reduces the noise made by the machine, which uses 30% less compressed air than grinders with conventional grips.
Mašinostroitel', Sep. 1973, No.9, p.26. Illus.

CIS 74-1994 Gallitz T.
Affections of the tendons in the region of the shoulder and elbow in moulders and fettlers
Tendopathien im Schulter- und Ellbogenbereich bei Formern und Gussputzern [in German]
Case histories and clinical findings concerning 111 fettlers and 56 moulders exposd to stress of the osteoarticular tissues caused by the continous use of pneumatic tools. Decription of the symptoms in 6 cases of cubital and 3 cases of scapular tendon disease; average exposure was 20 years, i.e. much longer than the average for the group of subjects examined. Mobility of the spinal column was normal, but radiography showed in 7 of the above-mentioned 9 cases a degree of arthrosis or osteochondrosis. The frequency of cases with clear radiological findings (33%) is considered characteristic.
Arbeitsmedizin - Sozialmedizin - Präventivmedizin, Dec. 1973, Vol.8, No.12, p.282-285. Illus. 14 ref.

CIS 74-1883 Cvetkov D.L.
Vibration-induced changes of enzyme activity in blood and organs - Vibration-induced changes of protein metabolism and nucleic acid metabolism
Promeni v enzimnata aktivnost na krăvta i organite pri vibracionno văzdejstvie - Promeni v beltăčnija obmen i obmena na nukleinovite kiselini pri vibracionno văzdejstvie [in Bulgarian]
Literature survey of enzyme activity and metabolic disorders observed in humans and animals exposed to vibration.
Letopisi na higienno epidemiologičnite instituti, 1973, Vol.7, No.39, p.153-163. 35 and 51 ref.

CIS 74-1587 Sautarel E.
Vibration-induced finger syndrome (with reference to a case study)
Le syndrome digital des vibrations (à propos d'une observation). [in French]
After describing the case of a logger using a chain saw and data from the relevant literature, this MD thesis deals with the vibration-induced finger syndrome which, depending on the authors, is either restricted to paroxysmal vasomotor crises of the type found in Raynaud's syndrome or else is associated with vasomotor and neurological disorders: background, occurrence, clinical study, special examinations, anatomy, pathology, aetiology, physiopathology, treatment, prevention and compensation. The author advances the hypothesis that peripheral neuropathy induced by prolonged exposure to vibration could be the source of the vasomotor disorders (Raynaud's phenomenon being only one of the finger syndrome symptoms) and would thus merit recognition as an occupational disease.
Université de Paris VI, Faculté de médecine Broussais - Hôtel-Dieu, Paris, France, 1973. 58p. 58 ref.

CIS 74-1584 Warburton G.B., Scanlan R.H., Wardlaw R.L., Karnopp D.C., Northwood T., Snowdon J.C., Sadek M.M., Tobias S.A., Junger M.C., Vér I.L., Eshleman R.L., Carmichael J.B., Von Gierke H.E.
Isolation of mechanical vibration, impact, and noise.
Proceedings of a colloquium held at the ASME Design Engineering Technical Conference (Cincinnati, Ohio, Sep. 1973), comprising papers on: reduction of the vibration response of complex structures; reduction of flow-induced structural vibrations; active and passive isolation of random vibration; isolation of building structures from ground vibration; isolation of machinery vibration from non-rigid substructures using multiple antivibration mountings; reduction of machine tool vibration; effectiveness of resilient elements for noise versus vibration control; reduction of noise by acoustic enclosures; high-performance shock isolation systems; biodynamic applications regarding isolation of humans from shock and vibration.
AMD-Vol.1, American Society of Mechanical Engineers, 345 East 47th Street, New York, N.Y. 10017, USA, 1973. 270p. Illus. 226 ref. Price: US-$25.00.

CIS 74-1582 Metljaev G.N.
Occupational hygiene and health problems among concrete workers on construction sites of large hydroelectric power stations
Voprosy gigieny truda i sostojanie zdorov'ja betonščikov, zanjatyh na stroitel'stve krupnyh gidroėlektrostancij [in Russian]
Concrete workers employed in the construction of hydroelectric power stations are exposed to many hazards, the most important of which is vibration due to concrete vibrators. An analysis of sickness absenteeism showed that the chief causes were upper respiratory, gastro-intestinal tract and nervous system disorders, as well as pyoderma. Recommendations for the improvement of conditions of work include: prohibiting the blasting of concrete surfaces by compressed air and the use of certain types of vibrators; using remote-controlled vibrators or vibrators with antivibration handles; introducing 10min pauses after every 2h work period to reduce fatigue.
Gigiena truda i professional'nye zabolevanija, Dec. 1973, No.12, p.8-11.

CIS 74-1272 Buchancová J.
Possibility of using hippuran ¹³¹ iodine in measuring peripheral circulation in occupational vibration disease
Možnosti použitia tkaňového clearance hippuranom ¹³¹ I pri vyšetrení periférnej cirkulácie u profesionálnej choroby z vibrácie [in Slovak]
Article describing how peripheral circulation was measured by the method of observing tissue clearance of hippurane among a selected group of 32 patients suffering from vibration disease, with angiospastic or angioparalytic vascular changes predominating. The radioactive substance was administered in 0.2 ml (1.5 µCi) and injected subcutaneously into the dorsal part of the middle phalanx of the finger. The rate of decrease of radioactivity was plotted graphically. Using as a basis the time required for the level of radioactivity to fall by 1/3, the author determined the patient's resorption capacity. This capacity showed a marked falling-off under the effects of cold in patients in an advanced stage of the disease.
Pracovní lékařství, Feb. 1973, Vol.25, No.2, p.46-50. Illus. 12 ref.

CIS 74-1270 Anitesco C., Bubuianu E., Contulesco A.
Interaction of catecholamines and electrolytes in industrial noise-vibration injury
Interaction des catécholamines et des électrolytes dans le traumatisme sonore-vibratoire industriel. [in French]
Description of investigations carried out among 100 workers engaged in locksmith, welding, riveting and assembly work, using vibrating tools (600-2,000Hz) and exposed to noise levels between 82 and 86dB, rising to 105dB in certain circumstances. The results were compared with those of 20 controls. A significant increase in the urinary excretion of catecholamines (adrenalin and noradrenalin) and potassium among exposed workers shows an increase in the activity of the sympathetic nervous system. Bilateral deafness was observed in 48% of the cases.
Archives des maladies professionnelles, Sep. 1973, Vol.34, No.9, p.503-510. Illus. 12 ref.

CIS 74-1269 Medvedovskaja C.P., Parljuk A.F.
Functional state of the visual analyser of persons exposed to low-frequency vibrations and jolts
O funkcional'nom sostojanii zritel'nogo analizatora u lic, podvergajuščihsja vozdejstviju obščej nizkočastotnoj tolčkoobraznoj vibracii [in Russian]
Results of ophthalmological examinations carried out on 84 crane operators exposed to jolts resulting from the operation of overhead travelling cranes: angiodystonic changes at the retinal vessels and slight reduction of visual field when compared to a control group; light and colour sensitivity thresholds were 50% higher than among the controls. This reflects circulatory disorders of the brain. The authors stress the necessity of carrying out ophthalmological examinations on all workers exposed to vibrations and jolts.
Gigiena i sanitarija, Nov. 1973, No.11, p.42-46. 10 ref.

CIS 74-1266 Bjurvald M., Carlsöö S., Hansson J.E., Sjøflot L.
Whole-body vibration: a technical and physiological study of work postures and drivers' seats
Helkroppsvibrationer: en teknisk-fysiologisk studie av arbetsställninger och förarstolar [in Swedish]
Mechanical and physiological effects of whole-body low-frequency vibration were studied in male subjects in different standing positions and sitting on different seats. The subjects were exposed to vertical and lateral sinusoidal vibrations at frequencies of 1.5-8.0 Hz and root mean square acceleration levels of 0.16 and 0.28g. Electromyographical recordings showed some characteristic muscle response to vibration exposure; increased oxygen uptake and pulmonary ventilation occurred in the natural frequency range of the body. Acceleration measurements at the head, shoulder, chest and hip showed characteristic body response for different postures. The seat design proved to be of particular importance for the vibration transmission to the body when exposed to lateral vibration.
Arbete och hälsa - vetenskaplig skriftserie, 1973:7. Arbetarskyddsstyrelsen, Fack, 100 26 Stockholm 34, Sweden, 1973. 27p. Illus. 22 ref. Price: Swe-cr.6.00.

CIS 74-1254 Ševčik M., Runštuková J., Hanák L.
Damage caused by vibration and noise in forestry workers in Southern Bohemia
Poškození z vibrací a hluku u lesních dělníků v Jihomoravském kraji [in Czech]
Account of examinations carried out on 183 Czechoslovakian forestry workers (mean age 36 years, mean length of service 6.6 years, daily exposure time 1 to 6 h) using chain saws. The authors found 120 cases (65.5%) of vibration-induced disease, generally discrete, and 83 cases (45.5%) of traumatic vasoneurosis of the 1st and 2nd degrees. Neuropathological findings were observed in 61.8% of the persons examined. Orthopaedic examinations (particularly X-rays of the hand and wrist skeleton) disclosed disorders in 24% of the cases. 35.5% of the persons showed a general impairment of the motor system. An ear, nose and throat check and audiometric test performed on 149 persons disclosed a slight lowering of auditory acuity in 38.6% of the workers.
Pracovní lékařství, June 1973, Vol.25, No.6, p.244-248. Illus. 21 ref.

CIS 74-1253 Drobný M., Geryk B., Fundárek J., Klincková E., Buchancová J., Galíkova E.
Vibration-induced disease of the upper extremities and its clinical and electrophysiological manifestations
Choroba z vibrácie na horných končatinách a jej klinické e elektrofyziologické prejavy [in Slovak]
The syndrome of sensorial polyneuritis was diagnosed in 56 subjects with an occupational history of exposure to vibration. The most severe symptoms were found in forestry workers using chain saws. Light lesions of the peripheral neuron were clinically determined in 13 cases. These manifested themselves by a significant reduction of peaks in the EMG during maximum contraction and by a significant decrease in the motor fibre conductivity of the ulnar nerve. The subjects who were affected only by sensorial neuritis also showed a decrease in motor fibre conductivity. The authors see in these EMG anomalies subclinical symptoms of an inapparent form of motor neuritis. No relationship could be established between the frequency of lesions of the cervical spine and the joints of the upper extremities as shown by radiography on the one hand, and lesions of the peripheral motor fibres on the other.
Pracovní lékařství, May 1973, Vol.25, No.5, p.185-189. Illus. 20 ref.

CIS 74-1289 Manjašin J.A.
Disturbed urinary excretion of metabolites of aromatic amino-acids in persons exposed to vibration and to very high frequency electromagnetic waves
Troubles de l'élimination urinaire des métabolites des acides aminés aromatiques chez les personnes exposées aux vibrations et aux ondes électromagnétiques de très haute fréquence. [in French]
French translation of: Naru¿enie vydelenija s močoj produktov obmena aromatičeskih aminokislot u lic, podvergaju¿čihsja vozdejstviju vibracii i ėlektromagnitnyh voln sverhvysokoj častoty. Gigiena truda i professional'nye zabolevanija, Moskva, USSR, Aug. 1967, Vol.11, No.8, p.47-49. 11 ref. Urinary excretion of phenolic compounds was investigated in 3 groups of persons (group of controls, of persons with vibration injuries, and of persons exposed to very high frequencies). The urine phenol level was found to be increased in persons affected by vibrations and by very high frequencies (VHF) at field strengths of 15 to 20 µW/cm². This phenomenon is attributed to the disturbing effects of noise, vibration and radio frequencies on adrenal and thyroid hormone function. The increase in phenol excretion noted in persons with vibration injuries was directly proportional to the extent of the lesions.
Translation INRS 118 B-73, Institut national de recherche et de sécurité, 30 rue Olivier-Noyer, 75680 Paris Cedex 14, France, 1973. 5p. 11 ref.

CIS 74-1006 Basic environmental testing procedures. Part 2: Tests - Random vibration wide band.
Essais fondamentaux climatiques et de robustesse mécanique. Deuxième partie: Essais - Vibrations aléatoires à large bande. [in French]
These 4 publications define the general requirements which should be met by components and materials which are, in use, required to withstand specified severities of random vibration within a wide band. The first describes the layout of the test methods (mounting and control, vibration severity, degrees of reproducibility, definition of sinusoidal vibration, initial and final measurements) and mentions in appendices the considerations on which the random vibration wide band test is based. The 3 other publications contain detailed specifications relating to 3 possible degrees of reproducibility (high, medium and low), and describe the respective confirmation methods.
Publications 68-2-34, 35, 36 and 37, International Electrotechnical Commission, 1 rue de Varembé, 1211 Genève 20, Switzerland, 1973. 35, 47, 47 and 27p. Price: 36, 45, 45 and 27 SF.

CIS 74-1002 Collins A.M.
Decrements in tracking and visual performance during vibration.
Literature review concerning the decrements in human performance on tracking and visual acuity tasks during vibration in terms of frequency, acceleration and direction of vibration. Vertical, longitudinal and lateral vibration as well as the effects of other variables are discussed; an hypothesis is offered for translating experimental results into predictions of performance decrements for workers in vibrational environments.
Human Factors, Aug. 1973, Vol.15, No.4, p.379-393. Illus. 34 ref.

CIS 74-995 Hansson J.E., Suggs C.W.
The effect of low-frequency vibration on control capabilities in drivers
Lågfrekventa vibrationers effekt på reglagemanövrering [in Swedish]
The effect of sinusoidal low-frequency vertical vibrations on work with pedal and hand lever controls was studied on 10 male and 10 female volunteers under standard conditions. The results show that control capability is affected already at frequencies of 2-2.5 Hz and vibration amplitudes of 10 mm. The factors "work position" and "control resistance" had a significant effect on the results of tracking tasks. The best results for work with levers and pedals in respect to tracking error amplitude, offset, delay and accommodation time were usually obtained with control resistances of 0.5 to 2.7 kgf for the levers and of 2.3 kgf for the pedals. No differences were found between work with the left and right levers.
Rapport nr 63-1973, Royal College of Forestry (Skogshögskolan), Stockholm, Sweden, 1973. 22p. Illus. 10 ref. Price: Swe-cr.5.00.

CIS 74-935 Hansson J.E., Klusell L., Krantz S., Ohlsson G., Petersson N.F.
Percussion power drills - An ergonomic and occupational hygiene study
Slagborrmaskiner - En ergonomisk-hygienisk studie [in Swedish]
Report on an ergonomic and occupational hygiene study of 7 different power drills under standard conditions. The study covered design, handle vibrations, noise levels and airborne dust concentrations. Measurements were made of work heaviness and force requirements, as well as a subjective evaluation of the tools. The results are given in tables and graphs. Noise and vibration levels were high. The dust levels were higher for pneumatic drills than for electric ones. A proposal for prototype testing is made. English translation available.
Uppdragsrapport D:nr 21/72 S, Arbetarskyddsstyrelsen, Fack, S-100 26 Stockholm 34, Sweden, 1973. 42p. Illus. 18 ref. Price: Swe-cr.7.00.

CIS 74-991 Griffin M.J.
A survey of human response to vibration research in Great Britain.
Results of a questionnaire survey conducted by the Human Factors Research Unit of the Institute. The replies received from 57 research groups are tabulated and include details on: vibration simulation facilities available for investigating human response; portable vibration recording systems and vibration analysis facilities; laboratory and field experiments conducted between 1965 and 1970 and since 1970; reports and theses published between 1965 and 1970 and since 1970; estimates of numbers of research workers involved in investigations relating to human response to vibration; projects to be continued, and those started, during the year beginning Oct. 1972. The distribution list for the questionnaire and the replies received are included.
ISVR Technical Report No.60, Institute of Sound and Vibration Research, University of Southampton, United Kingdom, Mar. 1973. 57p. 77 ref.

CIS 74-703 Kákosy T., Szepesi L.
Effects of vibration exposure on the localisation of Raynaud's phenomenon in chain saw operators.
Analysis of the distribution of Raynaud's phenomenon due to vibration in 4 occupations exposed to local vibration (chain saw operators, pneumatic hammer operators, tool grinders, stone cutters) with regard to complaints and objective cold provocation tests. Of the 485 workers examined, 158 had Raynaud's phenomenon. The symptoms and signs in pneumatic hammer operators and tool grinders were distributed symmetrically; the radial side of the hand was most affected. In chain saw operators, Raynaud's phenomenon appeared mainly on the ulnar side of the hand. It appears that finger lesions due to vibration vary within each occupation; the most asymmetric distribution was found in stone cutters. The acceleration (in m/s²) was measured in chain saw operators at different points of the back handle; it was highest on the most affected fingers.
Work - Environment - Health, 1973, Vol.10, No.3, p.134-139. Illus. 16 ref.

CIS 74-698 Levin G.
Some remarks on "pneumatic pick disease"
Einige Bemerkungen zur "Abbauhammerkrankheit" [in German]
A description of occupational "pneumatic pick disease", which occurs in work with specific tools and machines that produce rhythmical rebound concussions or rapid vibrations on the part of the body used to hold or prop these tools. Pneumatic picks are the main cause of this disease in mining. The recoil of pneumatic picks is mathematically analysed, and damping devices are considered. It is suggested that the existence of a personal predisposition should also be taken into account.
Kompass, Sep. 1973, Vol.83, No.9, p.219-222. Illus.

CIS 74-687 Sommer H.C., Harris C.S.
Combined effects of noise and vibration on human tracking performance and response time.
Vibration has already been shown to be the major cause of performance decrement in studies of the combined effects of noise, vibration and heat on human tracking performance and reponse time. The purpose of the present study was to test 12 subjects for a longer period of time, with lower noise and vibration levels. The results parallel previous findings and give support to a subtractive interaction interpretation of the combined effects of noise and vibration on human tracking performance.
Aerospace Medicine, Mar. 1973, Vol.44, No.3, p.276-280. Illus. 5 ref.

CIS 74-406 Zepler E.E., Sullivan B.M., Rice C.G., Griffin M.J., Oldman M., Dickinson P.J., Shepherd K.P., Ludlow J.E., Large J.B.
Human response to transportation noise and vibration.
A historical review of research carried out during the period 1963-1973 at the Institute of Sound and Vibration Research, Southampton, United Kingdom, on a number of aspects of human response to transportation noise and vibration. Individual sections are devoted to: sonic boom; subjective acoustics tests procedures; human response to vibration (vibration and vision, subjective response to vibration, physical response of the human body, vibration experienced by man in vehicles); effects of noise on performance and comfort; development of a mathematical model to determine the economic impact of achieving reduced community noise levels from aircraft; community noise studies.
Journal of Sound and Vibration, 8 June 1973, Vol.28, No.3, p.375-401. Illus. 52 ref.

CIS 74-396 Šimková V., Gomboš B.
The occurrence of vibration-caused disease in iron-ore miners
Výskyt ochorenia z vibrácií u baníkov železnorudných baní [in Slovak]
Between 1959 and 1970, 372 cases of vibration-induced disease were diagnosed in Slovakian iron-ore miners. The occurrence of the disease is related to the use of high-frequency hammer drills, and also to the relatively cold environment in wet drilling. Young workers are more susceptible. Changes noted: vascular lesions with spastic manifestations, usually of a bilateral nature; cervical spine disorders revealed by radiography; less frequent lesions of the bones and joints of the upper extremities. 68.3% of the persons concerned were assigned other duties; after 5-10 years, only 50% of them showed any signs of improvement.
Pracovní lékařství, Mar. 1973, Vol.25, No.3, p.104-108. Illus. 20 ref.

CIS 74-383 Dudek R.A., Ayoub M.M., El-Nawawi M.A.
Optimal work-rest schedules under prolonged vibration.
Research was conducted into the performance and recovery characteristics of men subjected to low-level, whole-body vertical sinusoidal vibrations for 1-2 h periods. Several subjects performed a vertical compensatory tracking task using a CRT display according to 3 work-rest schedules in both normal and vibratory environments. The working period was divided into equal intervals during which performance was continuously monitored. Results and conclusions are presented regarding performance decrement and recovery under varying work-rest schedules. Optimal work-rest schedules and implications for control tasks in a vibratory environment are discussed.
Ergonomics, July 1973, Vol.16, No.4, p.469-479. Illus. 36 ref.

CIS 74-382 Sjøflot L., Suggs C.W.
Human reactions to whole-body transverse angular vibrations compared to linear vertical vibrations.
An experimental study of the effects of various forms of angular motion in the transverse mode and a combination of angular transverse and vertical motion, common in ground vehicles. Heart rate, tracking error, hip and shoulder acceleration, and subjective judgements of 3 subjects were recorded under different test conditions using 3 different seats. It was found that man is more affected and shows more degraded performance under the influence of transverse angular vibration than under vertical vibrations alone. Combined transverse angular and linear vertical vibrations produce the worst condition. Tractor seats which are suitable for vertical vibrations are not necessarily good for transverse vibrations.
Ergonomics, July 1973, Vol.16, No.4, p.455-468. Illus. 17 ref.

CIS 74-185 Amphoux M., Gentax T., Poli J.P., Sevin A.
Kienböck's disease - An occupational accident?
La maladie de Kienböck: un accident de travail? [in French]
The authors examined more than 30 cases of Kienböck's disease among building and civil engineering workers. Only 4 of the patients examined had been exposed to low-frequency vibrations due to using a pneumatic hammer; nearly all, however, suffered from relatively frequent occasional trauma. In the majority of the cases, Kienböck's disease is the result of an unnoticed fracture. Immediate diagnosis of the osteonecrotic lesion of the lunate bone, exceptionally bilateral, is possible only with the aid of profile tomography, although local pain on palpation of the posterior horn of the lunate bone should arouse suspicion of the lesion. In more than 50% of the cases, tomography reveals fracture lines or multiple fractures.
Archives des maladies professionnelles, June 1973, Vol.34, No.6, p.309-320. Illus. 5 ref.

CIS 74-133 Mouton-Liger J.
Diseases of the eyes - Physiological and pathological influences of radiations and vibrations on the eye and visual function
Ophtalmopathies - Influences physiologiques et pathologiques des rayonnements et vibrations sur l'oeil et la fonction visuelle. [in French]
Studies briefly the traumatic effects on the eye of the principal radiations and of acoustic vibrations, indicating the most exposed occupations. Electromagnetic waves (short waves and radar), infrared, visible spectrum and ultraviolet radiations, X-rays, lasers and sound vibrations, infrasound and ultrasound are considered in turn. The shorter the wavelength, the more penetrating and harmful the wave action. Thermal waves, electrical waves and sound waves have a more marked effect on the visual function than light and ultraviolet rays, X-rays, etc., which have a greater traumatic effect locally.
Médecine et collectivité, July-Aug. 1973, No.7-8, p.7-14. Illus. 11 ref.

CIS 74-113 Dupuis H.
Present state of development of measurement technique and evaluation of mechanical vibrations
Über den Stand der Messtechnik und der Bewertung mechanischer Schwingungen [in German]
Discusses briefly the points of application and directional characteristics of body vibrations to be taken into consideration in testing for mechanical vibrations at the workplace. Information is given briefly for persons operating the measuring instruments and concerning the instruments themselves. The evaluation criteria for whole-body and hand-arm vibrations, according to the German VDI directive 2057 and ISO standards, are compared in detail. As a consequence of closer relations between nations, compulsory international standards on vibration measurement are necessary.
Zentralblatt für Arbeitsmedizin und Arbeitsschutz, May 1973, Vol.23, No.5, p.138-143. Illus. 6 ref.

CIS 74-106 Cummings A.
End-plate vibration in exhaust silencer chambers.
An examination of the behaviour and effects of yielding silencer endplates. A theoretical model is proposed and compared with the measured behaviour of an actual end-plate. It is concluded that the behaviour of silencer end-plates can be accurately predicted; a theoretical model may thus serve as a quick check of silencer design.
Journal of Sound and Vibration, 8 Oct. 1973, Vol.30, No.3, p.367-372. Illus. 5 ref.

1972

CIS 75-67 Portable power tools - Permissible vibration levels
Mašiny ručnye - Dopustimye urovni vibracii [in Russian]
This standard, which entered into force on various dates between 1 July 1972 and 1 Jan. 1975 for various types of portable power tools (pneumatic picks, mine drills, portable grinders, nut runners, etc.), prescribes the permissible vibration velocities in m/s and effective levels in dB for 9 octave bands from 8 to 2,000Hz. It also stipulates that the force applied by the operator on the tool should not exceed 200N (20kg), and that portable power tools should not weigh more than 100N (10kg).
GOST 17770-72, State Standards Committee (Gosudarstvennyj komitet standartov), Moskva, 1 July 1972. Izdatel'stvo standartov, Novopresnenskij per. 3, Moskva D-22, USSR. 3p. Price: Rbl.0.16.

CIS 74-1262 Schumacher H.R., Agudelo C., Labowitz R.
Jackhammer arthropathy.
Severe wrist arthropathy with bone fusions and milder elbow and shoulder changes are reported in a 59 year-old jackhammer operator with 30 years of service. The authors conclude that arthropathy as well as vasospastic phenomena may be considered as an occupational disease in pneumatic tool workers.
Journal of Occupational Medicine, July 1972, Vol.14, No.7, p.563-564. Illus. 6 ref.

CIS 74-388 Crocker M.J., Hamilton J.F.
Machine isolation for noise reduction.
Paper presented to the Purdue Noise Control Conference (Lafayette, USA) in July 1971. A simple model is used to illustrate the main characteristics of a machine-suspension system and to discuss the measures which may result in a reduction of the noise generated by the machine. 3 examples are given of the use of vibration isolators in actual practice, the selection of isolating material and the mounting of isolators.
Noise and vibration control engineering. Ray W. Herrick Laboratories, School of Mechanical Engineering, Purdue University, Lafayette, Indiana 47907, USA, 1972, p.203-208. Illus. 13 ref.

CIS 74-387 Ruzicka J.E.
Fundamental concepts of vibration control.
Paper presented to the Purdue Noise Control Conference (Lafayette, USA) in July 1971. The author defines the nature of vibration excitation associated with various dynamic environments and discusses the performance characteristics of common methods of vibration control (particularly isolation and absorption and structural damping) with emphasis on their practical application.
Noise and vibration control engineering. Ray W. Herrick Laboratories, School of Mechanical Engineering, Purdue University, Lafayette, Indiana 47907, USA, 1972, p.170-181. Illus. 26 ref.

CIS 74-384 Crocker M.J.
Noise and vibration control engineering.
Proceedings of the Purdue Noise Control Conference held at Purdue University, (Lafayette, USA) on 14-16 July 1971. The conference consisted of 9 sessions, 5 of which are of special interest to industrial hygienists and design engineers: machinery noise (8 papers); industrial noise criteria and control (7 papers); vibration control and biodynamics (8 papers); noise and vibration control (9 papers); noise in buildings (10 papers). The papers are reproduced in full, and the volume is supplemented by an extensive bibliography listing all the references given in the papers.
Ray W. Herrick Laboratories, School of Mechanical Engineering, Purdue University, Lafayette, Indiana 47907, USA, 1972. 594 p. Illus. 600 ref. Price: US-$16.50.

CIS 72-2172 Ragu M., Roure L., Tisserand M.
Vibration in construction machines
Les vibrations des engins de chantier [in French]
Following a brief survey of the 3 ranges of vibration frequency and the disorders they produce, the authors review the research carried out at the INRS Nancy Research Centre on the reduction of construction-machine vibration-transmission to the driver: direct vibration measurements on various machines; studies on vibration-damping devices. Tests were made on 2 low-pressure-type wheeled loaders moving over construction sites at different speeds, loading earth and stones, levelling and crossing obstacles. Descriptions are given of the measuring instruments, the results and their evaluation.
Travail et sécurité, Mar. 1972, No.3, p.149-157. Illus.

CIS 72-2637 Okada A, et al.
Temporary hearing loss induced by noise and vibration
5 audiometrically normal subjects were exposed to (1) steady-state noise (101dB), (2) vibration (2 to 20Hz at 100 to 1000cm/s²), and (3) noise plus vibration. The main experimental conclusions were that exposure to vibration of 5Hz and 500cm/s² (5Hz being the resonance frequency of the human body) produces a significant temporary threshold shift, and that hearing loss from noise may under certain circumstances be increased by simultaneous exposure to vibration.
Journal of the Acoustical Society of America, Apr. 1972, Vol.51, No.4 (Part 2), p.1240-1248. Illus. 16 ref.

CIS 72-2531 Warnaka G.E., Miller H.T., Zalas J.M.
Structural damping as a technique for industrial noise control
Damping - which is not to be confused with attenuation - is defined as an energy conversion process in which mechanical energy is transformed into heat energy which is itself dissipated into the environment. It is a useful tool in noise reduction where structural resonance or wave propagation at sonic speeds is responsible for noise radiation. It is also useful in reducing noise originating from mechanical impact and from steady-state excitation. The application and effect of structural damping on noise abatement are illustrated by 5 examples (conveyor exit chute, vibratory feeder, plastic grinder, acoustic enclosure, and vertical turret lathe).
American Industrial Hygiene Association Journal, Jan. 1972, Vol.33, No.1, p.1-11. Illus. 15 ref.

CIS 72-2532 Holmer C.I., Lagace A.
Effect of structural damping on the sound radiated from impacted structures
In the first part of this paper, a mathematical model is developed to permit the estimation of the reduction in impact noise due to the addition of mass, stiffness and damping to an impacted system. The change in peak radiated sound pressure level from an impact is found to be proportional to the change in mass and stiffness of the impacted surface. The second part of the paper presents the results of experiments carried out on a foundry hopper before and after damping; there was substantial agreement between the calculated and measured energy noise reductions.
American Industrial Hygiene Association Journal, Jan. 1972, Vol.33, No.1, p.12-18. Illus. 1 ref.

< previous | 1... 14, 15, 16, 17, 18, 19, 20 | next >